Document p779xOLgve2pO4ZDEv9qem0w

Laboratory Report Cyprus Industrial Minerals Co. Research Division 2435 Mrirlary Avenue West Los Angeles. Calrlornra Telephone tL r 31 478-0462 NoFlrlr'e 8l-0237 KeY Beaverhead ore partj cles Roferencas: K. Harris report attached Dare or Report Z/ZZ/93 8yrDate of Wofk Flequest I V/14/gZ M. Kahn Fleported 8y P. Colville/K. Harris Agprcved By P. Col vi I ldc Copias: Expl orati on ER.S. Lamar B. Boudress File Slatus Compl ete Subtocl Samp'l es of hand picked partic'les logged as talc at the rig and under binocular microscope were sent for examination. 'Obteclrve Samples were studied by binocular microscope. wcpgtPaorheaeayalractrteGsil.ycdyElBewltIiotvsgiathhftilrushtoyeemesgrrflrolewehoteeoewinrlmleeidasm4suhneo0sd-gd5t.olr4ioaebwty(ve2,ilo(y56ruo'o-s4u3bl-ynv07dio't3e,aud)3s.l,c0Hefr.'-ooa3wmsX5eilrv'yta,heyre4s,dc0afriea'f-fwtn4rcua5hpmec'a)bdteriaotrwircnoeiltefhnssttehutahehdreailepnyfsdaiindrsstgheeiceolnelwretcnistcgae5adiw-llg,,e\r%e Particles from hole 4052 (130'-135', 145'-150', 155,-160,) are irregular mwcbctthahreahieaylibsctlwketrro.oeyhbkfsriameXtauelnrgilaixtmwptytueiaenidrtn.rehittasfiscfTtrhlogthaeherefcosaucftptiiwnraonerdelnegscrsepeeiensotermpcwtunue,dbdraeloceeireirflictcs.shcrathTosaislhlhbitoocteaowlrholipboettiohtekaw.eesldaTi,etahnhervndeae.idyrsvrdmesfbeeornrimscmeeotuiaeltwlsckoupihtlflefeiiaiktaettieherarlemlynytidaasoncetorletchafhgrtl.eiseoraeisrl1Naaittstsyeosooy.et.nmaSbleibeoksllmlewaegoeecrfean Tjdheernetiafiraebsleufbfiycitehnetcdoirfefelroegngceerss. so that the two minerals should be I am adding sorne pages out of Dana's mineralogy that give a quick test for Mgo. Tvthhaaeritecitrtyistoiosbbsneaorlvittee0dpsiana1mtcph-leeTwT. aaTlslhacehhamescaskseesdicvbreeyceSkri.sErto.oic'bI.kastlo.iteTsehoeecaicftutrasjcthweiisdthareAnpl0oprraatt1hsehCor-wTs than l'lg, and the photographs show some developrnent of a clay mineral. This CAM-44 SYPRUSITA-Alfaro000365 Page 2 Beaverhead Ore w(baseiiddeenlltijtfeie)d. as Mg vermiculite by Xray was not detected in but the may be a montmorilIonite samples selected. a \l P. Colvil le PClmh ITA-Alfaro000366 l-T.tir;rf, iEglSEsrD'*-= - (\J r<.r)t :h c., c! Ot LTJ .F trl I.r.l ITA-Alfaro000367 a E lrl Fo / o P ,P OJ c) AJ L rFo +J O o (J ? e. oE cJt lr, l! N FE st o Ii' o c! |r) (\l +L, {!-' .L|., +t-, P3- (\,, (\l (\J o rJt 9 = ut oE r.rl J Q L {J lrJ : I= oo t'i ul Lt lJ) 9 (J c|ro) i-l ro o r)$(\l L r..t +> P r.f) |l) ro Cf) lf, srrf) O ol- +J +'-.t rt) (\t C\J C! (\J tr) ro (\J C\I r.r) $t lr) r+ oJ rf) t- +J ort) F <f Ol () ol F\ Or (o cll t\ OJ o) c! <r O co C\l O (f) |r) (f) F\ l.- ro l.r) ro |r) F\ s (f) r\ ft F\ rt) 1.o sr F\ rlrl)) cc!! I |\ (a <(or F\ ro st@ (\J gl 6 l(r9, L! lrJ JlrJ o- t! = U' @ sf o (o rrt f.\ Lo O o r\(o ro (o O\ol (f) F\ Ol ir) r.r) rrt |(-o'. (o (oor lr) c! rr) (t rf) c.) rir rr) rr) tr) \\ i(to) o F st- srol O\or (o lr) ro rJ) co cn Ol ITA-Alfaro000368 , to redness and diooed toabead; thisoi6rahe use of soda the rvire contact with the pon en the heating pr6cess reral required, and the ity and more added if in the oxidizing flame :h case the color noted vith fusion, if it takes sh r@Neil (see p. 365) ti 'al has been added and the be Battend out n-Jh the and the remainder diluted lame.so that the escaping atrtatnedof material preseat; they .ifferent eolored beads :ducing flames (R.F.), colors are due. Com- (AIt.618). lc ilver, zine, etc. .iirnhsgmreaellna, mcooldu)n.t)' . g'r)o,-lcr-(eol)d.ldi-f -sa(tv(uvioriaoletleet.itl,.hhoot)t.). , or bluish green if highly tnet,od.ccooldlor-les(sr,edc,olhdo) t-). but mount; paler on coolinr. rall &rlount, - (yellorvish -rraterl (grecn, hot). cotd ). thystine-red, cold). "re"dJ. ,r" l. if sr.turated; CHE]TICAL EXA.IIINATION OF trIINERALS 369 s-im6il1lr7.toSathlot socf oPbhotaspinhsolrursv.ith- This flux givcs for thc most plrt rcactions borex. l'hc only cases cnunreiatcd here arc those-t'hich arc distinct, and hence those t'herc ihc flux is a good test. \\tith sr&:cales this flux forms a glcss in rvhich the bascs oT the silicate are dissolved,_ but the silicc itself is left insoluble. It appears as a skeleton readily seen flocting about in the melted bead. The colors of the beads, and the metals to rvhose oxidcs tbese are due, are: Color Bed- . Green. . . ................ Substance Chromium in O.F., hot- (6ne green rr.hen cold), Chromium in I\Ioll.lxlenum in O.f.). iOn .lFl..l'-a,,uddiRrty.F.g,irervehn,inhocotlldfin-e (red in O.F., green, cold - hot). g6llow-green Ursnium in R.F., cold: vellon-creen. hot. Yellow........, . . Violet. . . . . . . . . . Vanadium, chmme-grein in R.F-..cold qilrK ve[on'. Dot. D&ler on coohns. - (brorurish red, hot). In O.F., I\'Iod\r.nbdy,enguremen,'.1'helol6ti:ishhnegsrereeenn.i"cqo.l"d!1).., hot, paler on cooling - (ia R.F., Uraniuin-in O.F., hot; hot; green, cold). yeiionisL green, cold- (in R.F.,1-ellonish green, Vsnadiu:m brourrish id O.F., red, bot: dcahrrkomyee.sllroene,n.hcoot,ld-)p. aler on cooling - (in R.F., Tilanium.Qio,) in fi.n., yellor;, hod. (ejso in O.F., yenorr., hotl mlor- Iess, cold.) Ca.rnectonrsrrc REAcrroNS oF THE flrronreNr Er,rlrnNrs aliD oF Sotrp oF THErR Coupouxos .bef-o6r1e8.t.heThbelofrovlploipweinagldlisitncsoonmtaeincsastehse most chcmcteristic reactions, chiefly also in the rvet way, of the <lifiereni elemcnts &nd their oxides. It is desirable-for every student ii gain famililrity with thcrn by trial alrccdy becn bricfly with as mcny mentioned in tmheinperretlcsednisnqpopslqseibsle. .Fl\o{raan-}thoofrothueemhlvhafuvl6l . dcscription of thcse and other characleristic tcitJ(blo*'pipe end ot[erivise) leference should be rnade to the volumc by Brush and Pehdeld referred to on p. 361. It is to be remcmbered that n'hile the reoction of a sinqle substcnce m:r.v bc pcrfcctly distinct if alone, the presence of other substeices mny more o; alecstsuerlnteirxc:rlymionb{srtciounrcothf cmscinroer.rlclstiopnrcsc;auittioisnsco}nnsrcequetontlbycotbevkiconu,s that, and in thc special methods havc to bc <levisctl, to or.-crcorne the difficully erising frdm this cnuse. 'l'hcse rvill connection bc gatlcrcd fronr thc with the description of "eapcyhrosgpnecoisetsicinchPlnlrrcltcVrsof"th(iPsyrrv.o) rg[.iven in -Aluminum. The ltresence of rrlrrrrinrrrn in most infrrsil'lc nrincr:rls, contsinilq :r con- aideml)lc amortnt, rn:ly lrc dctcrtcrl lr-r' tlrc blrre color trhi,'h they trssurne when, trttcr Ininr hecIt*rthouetnaiaritstcte.ceh)Ldd.toos, rIirvlt')evhceeicortyhnny|roirhtaclthcocrlcsrtlrrlsf:ulIrrtsltlhmlotinlilrr"it\sltr.ettiiccptthrnrrii:retctrrildristnteicnc(w.rrfiturosiIlts"shnrciolr'stclntheriotntctlcctsrtrrlco,lrrht:hlirr'rrrlsirtrigirloo)ili;ilrrrulrr$nrsetnsioul(ocnlszrfortinrlrlrorbrcrnrrcintcnsl(rfitlrilnoirrcgIrsr'rrrlrtrritrrtir{rrncri'rr)inlilclgr,lirlrrrll:*rr'vcci.,t,lpbr'rgr.,ul,lr,,r-"llrr"g(licrrtcrcc.nglreoir.pi,exziisintekdltyteacelm.rrbImciTnltlr1ueIisrs1l,r.a:'lc1rloenlclolrso[fctroilcrrirrmsuisllrierctere,noln..tI omgllfrxlt(v"rnrterlrlA'$ctlr_ll,ntitrrrruvrt'lr)lir.intactlloaTnrnnth-ti!srrio1tcnun.n{boo-lgjnenr]v.hy'cAhct(cen.srnrd(ttni.rcdjcrttorlto)ri:.rtrrlnsn:llril.rr{csrrir.lrr|-rILomrlip,rni.svihricrrrt.rctxd\rrn.uficuttqlirsottrlrirlnrtxrroLtoc'[r.,ls:srrr1l.ttes(nsS'rus,-relbtlrsellopoinqarnIrirli,jrtcLolet)he'L:rpr(isrnso.tcolfolirltl.rr'rlr,rrirr;lrri.,rlrgterriiarrr)l.r.n6eogurtdCrrlrset.torrorrosltrrenrcr-.lersnavduyhlr.ipvtscshhruriio,llblclto,hlli,tsrmrrubrlcallltrrstilrsliecnlokufrrurlrritniqrethreaecpsosn..:f ITA-Alfaro000369 370 CIIEIIIC.IL I1INERrtLOCy In acid. nitric acid, comporrnds containing ..ntimony tleposit rvhite insolrrLlc n)et:rntimonic vr,J,ti$lt#,:{tri;i;,*i"*roiffii[*,iil:,:.',iiii$';l]:r,,i:JinJ_",1;l,ilr;;l; aagnni,d'"n"saortmiuser:trrhrisneein{*rirdis;eacsn;iilci.c'sfkfrilniir#.b.be"r:Tdrce.k,tictioic{tisJ:!pllg6r li;n:it.'ti',.-l.xi.li"i,-Jii*f^i""'1"la,l,o.it:.il""n".'*''l.l";"n;!,":;rln'"th"c1c*rorslend :tirlr,rtc*.ilIjn ;ffi xiilrly;'lftr,h,qesbiir!ia_1ncau"trents.l.q;_t1"A,Jyitiei*lrloi,rriv"i;s,ihiiir*gilr:ieitoelnntuciosituiotsr*uaritriloyn,"boii;'iil",;;"iJnr'"*;;f;lt;i;;lr"i'';iii;iri;."k:]' :ffiiiL; *ll b:rrium salts, e.xcepr t -i:d1'$lh:]f.il",'jl""? li,3l"11tfi,i;.;;rX u; til;i'"iiiy-.iriii"'ii"iipitate (Baso.) 6:pio1od",r.n)..*isiA,i:lus'?on,r..r*ih;yedn,ild,tr*e;i;,a;:ti'i;,x"il;:in#"i;t:iiT:;._,.Fii_i"fjfl!i!i!f'ri{t"*.JS:,i"1""tl"[.T":;Ll,i,'il,:T:::,l:i;:"1;,""",,1*H",::1*TL,T*,.,",;f iodide is obtoined; *:HT.*ilJil[. *neii:Li,.r ihe.ririnerr,l iii,ai,irying rteherrc. oc:rhtina!igisel.sil"ltro;.;;;-jd;;;,.-iJi[li"#'f l.Jj',1"".:1,*l$l; faw-bfucJit-rhnjBdlt.elo.ot'rnr.oeriezblt.c.lrpt'-)s"aoftrim"Jnttlgeapren"s""i*ytl.hiocieucaou,tfm"eladspmpo(flueaains"iiirnnitlsoitue_ium:cnr:omslneg*atai-I-l'i'ineenilneo.tg)irv.ieitoshtbr.'"rpiorfrg*'oe,te.nst;idJi(;ib,''.;?o,eor#;sT;;t';e6;iiis;.i",'j;i;i;un,i"il!s"',oto,r.1-oth,m"etTohsres,il,riesicirnr,ete:eei(3srn,.wc.doiia,trh,ot,orusliart;rep.r*,pnlehdlru$lrnrsli_c,l ;:fl*** *,.ff';l;i#;;;["il1"fii'"# i iiilli"t,,!'"]]':i'.ru:5ffiort,uonrm'rvaAu.ertcrmrdc*ici.e.ul\nupmvtcahe.pe(p-eenha'r9yp''mw,d!e\rrchr"o^aia.nccr"fhyNcnteito,cheroraaibacls,c.efibtuiaenemccei inmdirgniosinniositlt_euertnadilios.n.ng(ecca"oi:1bin.tbetti,it3notiarnlt:t;eci"n1sigi,j;slbfrirtoilip'-r;,hoo,Janlti'e#rcsili,,vlireiieir,t,gc,,,,..),,rg",nir*-'ernournthrersl:krf:lrrmlminueccb'rde).crsceotlimnonrc f,*'"In rreakly acid or iiil?J,lX?"",lilli|:t arkarine sosruultlitohnastecaisrciiu'im"iiiisiipiirJec'iilJirtiita'"tcied nmrro'r-verrrrrte by.the lrltrition of sorur.ions onry on ,hr_,e.esls"l.tc,uggara:rdsdrgobmfClootohim1n\em..al(tre.ect-.cd9O,id.si.icin".se_ihiticAocibthjex.ml)raew";o;n;caiml'lo";i;xa"';rinl;rrJjeryl"ef";rr,-e.ceo9qsnurg,loi,p,ri"-llcc",.rrlcctp"ot,rg"(,ir-irttrsti;nf,hrJico"lalris"r;-l.;tul".otir;ifr;;"c-"crir,rll*drJi:itr.r";nri;.iiirrl,"riilmr,i,iT,giiiiitviiiei,il,"ll.il"c."ihj'l,lri.:trihlc,eti.e,:,Lrlildslt,ttificftiio;s"lu-obf- - {D5eu,id',Ni'h"terni'h;iefai"teildiri"s"i,nTsttallntmlv sirrll,ii,."n'tt,liiUi*ll:liiliiuc r,, .iir,,.i,in, rrso.psro S-,.lr[nli"sto'ir'rlr;r;iolntc"onrroor.i'6eng"ii1"i"oJ"u,.icilrt':iir'iiil,l'ir,!liliftf;i*#ii;i:'iJ!':];,HilliTiiiir,i,',ii,,i"ltiiJl'l;iil:l"i,f,::liiil"fiillillill:l1;l:l,ilXir,:; ,*1!ii:'3f #;,-r3LfTlffn;,s:."jtlt bornx a lxnd rvhich (o.F.),is sotrrnv ro rc<t (hot) r!4 ff_itfil.1#iknt"iil)';;,iiiLi,."i?$l'i#:i,i' ,,1'illl,.{;i,,"."'.1[:" i.,i:;i"""1"1.,iii :o.,:tl:gfLbftoij:'fiDrl(,)c:,lrsf't-'etO(+l ntr'niicc,hh,aal,rrccloioi:l,rll.l.it:t,1lo:"rsut ,#,.:rrf"l*^l^l-lrl.^,I*lr-i,:1"',f.1,:,1Jil:l,Xt,l,,",irrii:l ii,llill: ;t,:ryi,1*;,ii;ij#'iilrl# jfi jxi:[]i:*ilL'r*Tr,lonpw:v1((rel.rr;e,r.l,,r,"..,'"iion trca<l ivhnir ti,lt. r,*'^l,,iijij,lj,,'lfirirticill,Jjr:riliilhlje{lln,:ilc1,T1o1i;dii;,l11^'.r.l\'1'ltt sotr:t. ..1\'irh lror:rx it nr.,rc<,l,isricevniiln)Ku'hrr,r,,):;L;"rs";t'e.;i;(ili'tlr')i;,.ii,c'.i'lit(.:ls,'ii.',,;iii',!i'.'Ltrr:ri,.li''ii,*i,.?1,',:,tiitli^,:i."i|;.,,1;iiili"",lli": *j.,i'i:L. .lli::i.l.i-:",1,-:"::ir1ilfi'rl|j|ltllciis;;tlliriol':rr;rlirirlrl,rl'l:,l1"isrhiollrrlil ,,"1*{,ulllltii:'j}uh.,ill,.J?;il?,lii,ilt'fi.r1.,]{il,,l;',i,5 nl.::"lsti;l,iifi$:", I t Fluninr pmduces a form a vola tll.".n dipp", Ivul apDeat Hiitd fuorite) giv overIraitns" h_i( when heata to brorrrnigb R.F. becom the edditior Ferric imn i cFnide is a ferri,cyanide. -r-aw. compounds; co. ating (Ph. orsappean, t In soluti delicary is n water added Lithium, resemblins ti the specuisr. Iilooncsiu color is obtai the addition , Droduces a rri hydroxide or Illangane' With soda (( rclied upon. r trIercurv.rniaer:rl is hq of metallic mr is obtrined. lIolfu)enr stain (O.F,), I for a moment The srlt of ph (RF.) a fine ; rsith sm.'rll scr sulphuric aciC bwmil'lnNmniscouknmd.ceo-odLt nickel. A sol: exccss. If an l sclrlet precil Ni&ium (l which slorvlt e iions rvith tle acidNthilemytcgs.iv-c Phosphonts brtn rnoistcno thc prc-"cnce of of rncllllic m: hv-tlAnrgfccrnt is gir drop tion of |rnrflrol] moll bd.rtc. ITA-Alfaro000370 uble nretrntimonic ]sted on chlrcortl, ' they give a lhite, e tr:ienrc Sultrnlue shen cold; airsenic re cloeed tube. In r a mirture of the R.F.) on cbarco ; snic, , rium sclts, e\cept on. rrccipitate (BaSOl) verv chlrr:rcteristic lso ;btsined ($'ith : in equal parts of trlimrte of bismuth re iodide sublimate rd red on er:posuFe rtes, datolite, dan'ned with sulnhuric . nosvdered riineral r.- The mixture is ;reen color apPan}, ish brosa color to ; the color changes an alkaline reaciion , the flanre by aomc re is a much deeper ] bv the addition of I silutions only on characteristic sub- . llow sith brosrr. . vieldine the odor- ;';d the Jdditiop of ric acid. chlorirle, nlso plto h copper oxirle, the 'ol coDDcr cnlonue. te of s'ifver chloride c aeid, but cntirely 'ow to recl (hol) and ,;nrheo. s-nChof.ruvsrninadOiu.mIr. rmes fmm mineurls hould first Lre thor- 'rluced from mo,qt of I l)c rotste(l first in '1r"l..)r, .if\\s'iathtrrrlnlttrral,xaint rlorirlc, olrtrrined bv tlre mincrrrl shoulil .'es s grc(,lr lllnte. excess paouuccs an CIIEUTC.C,L EXATTTNATION OF I\TINERALS 37L li;nf"ol[iru""iroon.dFfrtur5iltrc:a;err-ieoiv)i;nsrlAofitsnl*Iareiasvt.iwiilie.ir-nhoiciicfint"freio"rhmtctsevh-rrlrsbtr-;lc"ltrirnoltr-tiullrfuinlbr-ui:tlienriri'otrtcrtbntiohtc.oficd.af$.Brc,icS'cum.ild<toteil,s0ricn[r"rvdsit.ihohlolticc'uclt'bihhlhlb)coicsrmlrefttocrrsutrrrwuhointchedhidntlcihdlntcsporooisadtfthbutacteelsihpssaenehirnxuouctPu(mmrlolbio-ctscohnhevergdiisrcsmcrdtplrirtd,lralrp'oo,(trhlh]tlmmisereettlncolildtln.etloc"tv's&tnll)lodlgl3csc.lnouirptdmcsosoptwhfaope-dSulcaclinO(Otrldpczpscdprnn.lgtsr(tuuecehDce'ns9hE0es'' owt-;cRFoi'vyt-l".eaFir"b.rnrn.;Jmiieid"tb"tenic.iies.nrloc:i"ii-hs;onst;eimhc*adihe\"ndfsriid:ehnhi.em*bdiv"iioothl'-(bl;treri6tco,clac3eccr'neghso."idrlir*'omedctu'treo,iciinii"cinrltnguttcigrcr('tcttlsoirfodevl\srncIqatnisktuipohirr"sier-tlnuni\o.t3-tltbieerio0\thxvfynSreii)itannngh)ne'sivadcdhFbexistsceoflheeomrredasrrein{shxctfeleolsrpiirrstcraro'obromn:rblunreutouscgdeiuhtis-vine.bpm-iest(prr|soen.roccrcIo-fv.cbipblniioypmiefrfrilrettetnhctarcs-lertqfeic(w(&iOletohldy.le.td1ddYrn"rcr.tae)olmlo,tuwxonmoithda!a-loiecsgsloh.snoFplluelciousmtg(tilOcleyolseltnHme$s,lrll)-ourisosown.ys' dil';A&:;*ilf,'c#dw"e"oeo-Ia"neil;,iitiiocfIcfHilirrlfvr;|cr'i"a;j-Vii.;s,dnni^:ioldii,'gid;lS-l;eiu'seifSdtr:Vi.ieto:Otq-iointitth,;tsrfiii;er,;oietdtlt"rtsiillil."cotulL*-da;'trt-eiiGandetn"soes"srnt;xtliuitiiiocliiiclpitif;nsihJrh;6shtr;pirr"uutc"oelrmo]vifi,tco:eirtiih!lnflofall-eaioaetplcmw.nraimtdeseucOces:-irgddoenbll'clincuovbi-etrstre,be'-rosadnli\menY"dee-g&iirtnpelgl"leelrptl$otodr"cht.euhb,"hredectluitn".thhlie.enoeet'bosdopevissefteronohalemer)leidu'ytc;lh.ettioirspottoufemhtdlfnnttlleeisledairatce.else'lrvurfleqceleloladppousrrnoldhl-trdcernrildtuiaei'ntisenietaglte.o['hd-iUcgfbeil.sasistvamutcceoiionlhtespleroonioa8drrtamljbsrse.Deof[eroveeovimac;dsmeoselcvnl'anoshl-etatwo'ihiannet-ire-(dg'nntr tcti[-*brh"o'""*aeela;oItiisauo;r;D;r"*-il;id"i;o;ai;ci;tb;ti";orr;t-oa;n-o"s.i'cr-nhoo-eiaftpudnae.migiform*ronInv\omIiroiunrtlitimassutormuemo6npx"chertriy4*cliand,i*pftrareo"irt"fssatgsiiedblhierelnoeoheufiecnlideoa-lm|ttb.irgntepg[igvoe]rel,uegsrenmPrrdriioctsOehbvseeosrcdrf.doamf^nbivcErdd_isolgtetllr'nemnhgteis-ltrtlrnJleaentdstqeh(pl(O-'edrae.r'n9Ioc'd.)gi,p,bea1irntg1au:rdtcsienordtc(euiogbx)loyn.mrilcieIenmpsdnsms'oo(osaRlpuupn'rtFuriaonml)nek' rW'ro"erfilniimeteihdelr;at:saui;lor;liips]ci.rnf-m,i(e-Oeertvr.eeFcdniu.)rwiynit;ii,tlhipgienrievdctscrhelysoensascceeoldobtolsliuutelumidlsblmhteucobgaacrrscblsaeoiunrnbnbalYbrlctmeeKoa.atdn-ltu,ele;nsrtroehmtfrh-ilseeems[rsoleerp'osterucl+oltiitcotrxunbm]:erisetertvchoeeuIrrysynugdilpsDeh.l'lriicdreeaelotdegewiv&dneensnsd':hrrmeumnoa.Dyirtrehboqeer' igfTwJwtnHd"so-th-ili3ir"ioto,;lfcr:liiF,;rrfbInkihl.;m,sltmseioia1.(;;l.msloil.uo;n.itu.;i-lmoeFtrm;iAilLldl;'ife.ci;e')."sAnn;,;jsn'tc;utdo;hiai:rrc;|ltlol'nnuo\;ciipsi";,1drtuipl'riiocio-i.hfhbiln"ntt-t[ocil-eiup"ynJ.odidle--.oBr1Jll)onrtrncn!o.cudb'tolcrti*5ttecl,Jhn,oiain,t1&lir.iind-ic.wt,r.r;,tintciA"h",(,iote"U,",i",atLrt"n"e^i.or,'iitci,rf*!oco.moliF)oui"tfn.obitafi,."es"-icltlli"yciei'vencTyrbioEJsersglddiu*ctelirrl'v.rctoeoocthcncisfp$dCsoyusttidlsoshtmgaibriohouedluybvlf'eysigoeo-oiupra('cxlaerrcl]duoiptednnfeahat'ndweet.dritcidni:nhtodt(etgsli-rnitsi.pcnrosg-lipgphelraltioPiye)o(ddraerOlwvtao-)ntsp.lfenrr'oyrF]lmedd1enonr.drlc1l)rneetttrrrt"hoodi:er"sretrpDl:hhvarmseleltlimydhrcodioons(eleoacclmfecieuotmtaepwrinionroswsrrlauumntrshl&toiclaeeonttzsrryionfrarousidfcmsornsheroac(nyn-omxnctoDdnrtlocfitlntl,uee:ssndprreennsnoopo)tetdell;nrTuubtftriulluur-ltt.rturiienelloobelseeididcnndneo-oB"*ia*"both'fiitlo'hco"cvt"is*en'-d'ine'aciri*rnsllnlFrr"iiUi--rdi.t?irr,",hwt'a,ec,"";n;r,iescflitii,-,t-,rt;nnv,,i"ih]i;Di,ln"-,*ri;,rJiii",tisi-r.t.rc,cii,htiiiivgcrtqinr-crrcr;.itoirt"ipvii"frl,o";telilgiurotl;-uln'r^tr;nlt"isrmvl;tnrfrr*cwo;innls:bil\l,hrrTtcri,iris'llutr,rrncrtssrrfrmorlorclrotr"relrln"Strtrlp),(ntpmrrr-;,.o)ettliohrrqtixsclnno'tt1n-dtstgs:rrroivr.otipczcteefnctlliArrllron-),girlaavunilnticlcet,rs,rscsctilrto":,r'ltlocr,sl.rtl,lir,tirsri.(rril\trnt''vsl't.ltn,rilliir,tfrtrrrs,'i:ll;rri.Jrcn(ufrllotrltrctricI,ttll,otllqfrirdliccltrslxtr'lcrcioryoiiorbrrgry.ntilgtrntorehtveyrlricerlicarbc(iseinnrhirlto{lltrglo{tliic|llcnrltrlcro,lct,lsgsv1(t6nltto'(cui'ntxFir:rllwrlllirrlr-lldrlcosltii.otlrlictvth'srstIi.hrllltltcltpl.rlrircl{t:n'tpor:r''rllteclltei:rrcet't'ruemdk*vnlsloslioa(iti.lccn(h,eof('rlncittuda'ris(tnnvd'lltlt.lu:ul|,c.i)rrgnlbrccnluclioleiyurrllntel'\l,lir'wivslcurtlpcllirrrl'ratsrr''thti'ofitltbitsc'nslplllpc'rrrhu.brtltsreeEh\gorrtrsmhrrcrsv)pecuo''iebrratrleblrnoiocugcdyrf--' molybtlatc. ITA-Alfaro000371 372 cllotrrcAr, ITINEILALocY obsPeortvcsesdruthmr.o-usbPoatabsluheimelpis:srtsfiltaerviwolheitchcorlotirll to the flame n'hen alone. The flame is eliminrte the sodium flame color which best n'ill almos! invrriab'iy be presdnt. It is best detected in small quantities, or when sode or lithia idsl.p'rsrSereesleeeannibti.mleb-.vo-rthsaeOnnaicidcohoadfrocthro;eatlhsdDeeelsecuntrbioulismmc:ofrutpesee-osnSeeaceshiaalvlrs,coogaipvl.ini3seG-v{oo' flratbilreo,sanndfumnheesnwhitehatredpe(cRu.lFia.)r gvei-a 6ne ezuie-blue flame. On plaster gives red to critnson vohtile sublimate $ith char- actenst lc odor, of -.Sr&'con. A smrll fragment of silica. the bases beins dissolved. IUosi silicstes are iisoluble in a silicate in the sait of phosphorus acids. The fine powder ol such bead leaves a skelelon a silicate is fused rith sodium carbonace and the mass then dissolved in h-rdrochloric acid and evaporated to dry- aess. the si.lica separates as a gelatinous mess antl on evapomtion to dr1'ness is msde insol- uble. Il'heo strohe hvdrochloric .rcid and then nater is added to tbe dry residue in the test tube. tbe bnses are-diisolved lnd the silicr left behind. Itlanv silicates art directlv soluble in hvdrochloric acid, and l.he solution on evsporrtion will rield lhe characteristic silice iellv. Other silicctes rvhen trerted Nith acid are decom- poseil, the bases present going inio dolution, but the silica separ:lting and remaining sus- o'meanSvdeiqldresin.ne-rtdhleOv ulibqiehuaoirdbc.tooaTinlheiendreOb.vaFr.ehseqi:lrvrateidnragsliioovennsscabheabtrr$co'oenearnrl ictnhoeoRste.iFnt.gh,r.eeesApgegmcloiuabplulysle. of metallic silver if soda is added. Unlei some dircumstances it i! desirab'ie to have recottrse to cupellation. Fmm a solution containing any sdt of silver, the insoluble chloride is thronn dosa rrhen hydrochloric acid is addeil. this precipitate is insoluble'in acid or n'ater, but entirely so in arirmonia. It chanses color on erposuie to the lieht. r(rchf.icSbhtraotrnhitueiuvrmirc). iIv-eInCtocoomtnhpceeonubtnrladotswddro-rifnasentrfdolansmtliiigremh; tmlyaraednivulusiyueiaedllldysornleunctioaognlkrsrdizsientdreobnryetisutchmteiosfniunlerpfhtcearitrmeisgnonniil-tliroebnde pS' roemcSeiipdcirtoaumtrern"do-uonndCtshomeniprlldoudsniivtdieosnacnoonaf tlslaiusinllipinnhegurrsiecoxdacitcuioimdn (cf. calciunr and barium). give a strong and persistent ajter icnition. yellow flane. etdbteretiapSocuipbe6ldfpnhmbtivriob.ifsuStseuitnlonhenheJidvoeDlvistci:mehlSurdruscl6ndputaullrtn-li$enhsuei.trhr-.dsiIoolnndxaisdtheame,ndlwclllhcoqhsicauchdracnohtutaaibtlsibedasus,ocsomhtra.eriTsanuhcletspiruhfilusipdstheiecasdtoegms?iv,roesrss:o,urnflwfpdhsheuurndlrndshidsruoedrrbi;iseuismnrt sbulaloihkictsetahia-asotnhrthsebeseilnvefrorims ethd,lsisoplltarcineeddon(thaeclperaencasiulvtieorncmoiennationndemd ooisntepn.e3d0; 7amduissttinbcet exerciserl). A solution of a sulphate in h1'drochloric acid gives lvith blrium chloride a white insoluble D'feRuor.selFvicble,tilendeciLrtaiteunoteieuncnmoo,alf.orOmrb-lean'lsr'deisnuollmnalducs'resrotnreirdrrillsnrcrthhs(ra-tnect-.vehr[.3cc"st{itvuie5elrd.)rl.)riunOdrilncrthkcaehcbriordioDcosvcnanieltvlutlhosbcleiaytilgdcgieivvsccernrr&b,rclrrinrrr'lhlrrsriittlocccl.uoctoAriolgtsnirnl.atguyTils:lhthnaedmscucooboullolniomrtrad$tthieisle,-l diseprrear if acid is heatc,l too hot'or if on eoolinc. tater id ltkle,l. pot{?E'qlniu. m- cMyainneidrael,syiceoldntrrrinrcinhgrllictintin(e.ion..mcirnLrsr.tseitegrliotcb)u, lrcvsheurrr<hl erltervdhiLocn clrlrcorl n'ith anrl rlifficrrltly soda or vohtile oxide co:rting is formcd; the glolrulcs arc rnlllerble, but h.rrder thtrn silver. Dissolveti in nitric ncid, rvhite insolrrhle stlrrrric oxirlo scr)itrltcs orrt. whehaetTenidlocsrotiitulh,ml..aF-pTuicsitcetednoiwuf irmtnhctrgsriolrlicr,l:siutininlr.tchtrherelxltul.iIqr,:uirtircrvl irttihnrktsellslttl*isosvf ripoivllrccrxtrpl'choionlorrrr.hs-verrsl1rlonrccnclirrlrll.lr'1rvihc:ticfathccriisdpv,riroalilnaedtl evaf[ration. A yellorv to antlrcr col,,r rcirrlts rvhen hydrogcrr lrro.ride is arftlcd to a, sul- o' hurI'iucnngc'i!,,l Fused rntl srrlrrtion. rlrt.c-lrtcldirnrgsstlietunitotrxnirlc(rcgcirnaslioIvelr)lrrreritcholtolrretot(kthlitoiosnlltofozf inpcltoisltpsthco:tnrltsolfleiinnr,l (R.F.). gives a . ' 6ne blue color, 'fhe color clxtngcs to lrrriurr orr contintrctt rerlrtction. 'l'lrc color tlocs not 'vd'is(,esiiatshl.llaIotqUrIpr.,'nva)rpfoetelulnniJ.lulrdrievletrsitrtslrrrnurglsh,.,ry]sc.,,--lthnrrrr-,rer,.rrrtn'Urhrr(1\lecrevs\ao''oi(nscll0dhoioo,u)Illll'';<nm,u,1,rttrilr[oscrrnososrsn(;ie((rs(lllxcl.l,l.lnl',.lirrl.rllrrtr'r.rrvl:trtrlo;srr:1r,r.l.rl,tr:iirryll.crrloelcrfrr.ttbsrltirnre'.lrci,lrocsfth.lnic,jveiruoeolrilsrunltrtrr)lvilc.ttigrrtorxlrrdfrralryiusittqthlildo(l(tihsDrlTpvo.el3(ttlrotitii,tr.0rurg)ts.l)itcirbtlcute:nsrtdtltteqcc(iOnltttr.gu/Frlt.',to)rtvilattteltlgrl.lr-roel;er\s\nlil-istshho -1 I I yellZoiwnaw-hileObt. heatcd become when hested aI Zironiu* - oraag+yellor < - -.{r--i ,*:#H ill''.',:tt ftt*l 51e. general hesd depends mos cal chalocter There is mineral may complet set hand is refer until at last : -given is beyt A carefu.l ever, alwsys tion will oftt it should not with the apf The stud, once obviou-c htte, ckaoqe, not too srn.U gifractriytYst.al_sTbart distinguishin generally ver tence only $' talline form careful studl The first the pocket-k should be tb dered minen' c&rbD$te is follorv blol Pr if anv: the c the lir6td reti as cxphined Horv mut of his minen generlrl, trnd elcment$ry s If the result suggcst th$t. rnlry l)e ltr:r(t decisiou. ITA-Alfaro000372 llone. The flame is best m Ssue color n hich s-lll eq or n'heu soda or lithio nendfumsheesnwhitehstadD(Rcu.lli'a.)r tile eublimate n'ith char- us bead le.$'ea a skeleton r a silicrte is fused sith I and evanorated to drvto dryrresi is made ins;lhe dqr residue in the test r solution oa evaDoration 'ed sith acid are- decomting and remnining strs- ?IOUI)s. *iloiabliryleifofsmodeatailslicadsdilveed.r lation. :bloride is throm dorrn :id or water, but mtilely by the fine crimson-red r reaction aftr ontium sulpbate isnition ftll be numr. persistent yellow fame, ridea gile ofr sulphur; in stic odor and reddens g, lphateg sulphur uaec moss. $'nen sisoo,bluemst, 'rdnemdooisntepn.e3di:i7amduisstitnbcet 'hloride a. n'hite insoluble -e or gralish sublimatg iee.coActsinmgallanadmcooulnotr olution I'he color tho diswill ,rn charcoal with 'e and dilEcultlv soda or volatile .an silver. Dislolved in n a bead which is violet hydrochloric acid, and , especially after partial oxide is addcd to a sul- rhcuhonn lrcad (R.F.). orcuir.utTc.haed of tin, iivea a color does not s bad (O.f.) a greenish irot) fine gcrhemengi(ncgoktol).I-'e\ll\'xithr. 1 frgrn chrorrriunrl; nlso CUETIICAL EXAIIINATION OF TTII{ENALS 373 i"a1nwe'heaelZtlenoi(nnth'ebcnea.hc-tieoOlemdaesh3fotec$thr.hr.mronrecdooigsarrt'leheininetienntqh.oenNn_iortcehtoedo,rcrlhcioniobnd\rg\;'letafvlsaneondrl,rucmtthioco&noits.rnttehpneoeuzdninrblcsysoitlfihczeritneeco/gcfaiivlhfernsltoi,ncle"ot)itdtIi.inriegcon\rre.hsiirciblhrlui'riesi Ziraniun. oratrge.J.ellorv c-oloAr dilute lildrochloric acid solution, eontaining to turmeric paper, moistened by the solutioa. zirconium, imparis an DptrnrrrN.rrrvE trIrxERar.ocy 619. Determinative Minerr.logy mry be properly considered under the gneral head of Chemical lliner:riogy, since the deiermination of minerals depends mostly upon.chemicrl tests.-- But crystallographic and all tbe phlsical Tchhrerr:rectiesrsbuhat voenealseoxhtaoubsetivcearrevafuyll-yinobwshericvchd.the identity of an unknorvn minelal mry in all cases be flxed beyond question, end thaiis by the use of a complete set of determinative tables. By-rnecns of such tables ihe mineral in hand is referred succcssively from a gcneral group into & more special one, until e-t lnst all othcr_ specics havc been eliminated, and the identityof the ond given is beyond doubt. A careful preliminary examin&tion of the unknos.n minerel should. how- ever, rilveys be made before final recoume is had to the tables. This exemina- tion will it should often suffice to not be omitted, shorv what the mineral in hand is. and in,anv case since it is only in this \yay that a pr;cticel frimiiiaritv with the apperranc and characters of minerals ien be giined. The student will naturally take note first of those chiracters which are at once obvious to the senscs, that is: crysJcl line jorm, il distinct; qeneral struc- lure, ckauage, fratlure, Iuster, color (lrnd streal:), feel; also, if the specimen is $infoactvrtyiolsyota.rlsy'Ihaaelrl,cnthhaoerteapcprteeprsasernnetan, mtarenyddeitgfrrheatcoNtuf irlvelesriuyrgeugengseetqnuseoxrmlalielmythpui-nongerlseasnsecnteotia. {lhSeetrxucs-epcoetutcieiifn.c distinguishing variet ies; color and luster are esseniiel with metallic. but genercily very unimportant rvith nonmetallic minerals. Streak is of imnor- tance only rvith colored minerals and those of metallic luster (p. 271). Civstalline. form and cleavage are of the highest importance, brlt may require careful study. The first trial should be the determination of the hardness (for rvhich end the pocket-knife is often sumcient in experienced hnnds). The should be the determination of the specifc grauity. Treatment second trial of the oorv- dcrcd mineral rvith acids m&y carbonete is readily idcntified, come next;-by and :rlso other rtehsisulmtscoabntsai(nseeed.pp'T. hBe5ng, 860) a shoi,fJ folforv blorvpipc trials, t-o nscer!.lirr the lusibilitu; the color given to tfru n".". if rrny; tlrc chancter of tbc sublimale given off ilr thc iubes and on chereoaii thcmctal ro.hlccd on thelrrlter; thereactions rvith thcfures, and other pointi as explaincrl in thc preceding pogcs. Horv much thc obscrvcr lenr.ns in the nbovc u.:ry, in regerd to the naturc of his mineral, dcpends upon his knou'lerlge of thc- chrrncters of nrinerals in generul, :tnd upon his familiarity with thc chernic:rl belrin'ior of rhc l,arious elemen If the tery.subst:rnccs rosults of such with re:lgeurs :r prclirrrinlry and bcfor.e t lrc blos.pipe (pp. :l;'ig to 3{.ig). exlrminrti(,tr lrrc srjfncie;il-\- rlcfinite to suggest llrat tho nrinpnrl in rnly lxr rnetlc to tlxrir full hrrrrl is one of u dcscrilrtion in snrrrll nnrnlrr of sper:ir'.. PrLrt v of this rvorli loi rnfcrcnco thc firurl dccisi<-,u. ITA-Alfaro000373 Laboratory Report Cyprus Industrial Minerals Co. Research Division 2435 Mrlrtary Averrue West Los Angeles. Calrlornra Telephone t31 3t 478-0462 Frl,ng No R6ferenc6s: KeY Beaverhead ore particles Date of Beport 2/21/83 8y:Oate ot work Requesl .' n/ L4 /gZ lrl. Kahn RePorted BY K. L . Harri s As'ovadBY P. colville copas: Exploration R. S. Lamar T. R. Paul B. Boudress File Status S.E.l,l. Complete subrect Samples of Beaverhead particles logged at rig as having abundant tal c. Ob,ective S.E.14. examination to obtain micrographs and Xray analysis. Resul ts : Several hand picked particles were examined in S.E.F1. and EDAX spectrums were taken. Micrographs were taken at X5000 and X10000 of samples from the 145'-150', and 155'-160' levels of hole No. 4052. EDAX spectrums did not show the presence of l4g. Micrographs and EDAX spectrum included K. L. Harris KLH/hks GYPRUSITA-Alfaro000374 Page 2 Beave rhead ore particl es B. HEHVERHEFD 833. laz las nL:T ITA-Alfaro000375 Page 3 Beaverhead ore particles B: bEFVERHEHb 834'* tl-a-t LfttI ITA-Alfaro000376 Page 4 Beaverhead ore particles ft: BEFVERHEEb B3? tl-a-t lae ITA-Alfaro000377 Page 5 Beaverhead ore particles f,: tsEHVERHEHD 936 lt-az- la+ las ITA-Alfaro000378 Phyllosilicates EENS 2110 ulane University Prof. Stephen A. Nelson This document last updated on 08-Nov-2010 Phyllosilicates (Sheet Silicates) The phyllosilicates, or sheet silicates, are an important group of minerals that includes the micas, chlorite, serpentine, talc, and the clay minerals. Because of the special importance of the clay minerals as one of the primary products of chemical weathering and one of the more abundant constituents of sedimentary rocks, they will be discussed in more detail in the next lecture. The basic structure ofthe phyllosilicates is based on interconnected six member rings of SiOo-a tetrahedra that extend outward in infinite sheets. Three out ofthe 4 oxygens from each tetrahedra are shared with other tetrahedra. This leads to a basic structural unit of SirO.-2 Most phyllosilicates contain hydroxyl ion, OH-, with the OH located at the center of the 6 membered rings, as shown here. Thus, the group becomes SirOr(OH)-3. When other cations are bonded to the SiO, sheets, they share the apical oxygens and the (OH) ions which bond to the other cations in octahedral coordination. This forms a layer of cations, usually Fe+2, Mg+2, or Al+3, that occur in octahedral coordination with the O and OH ions of the tetrahedral layer. As shown, here, the triangles become the faces of the octahedral groups that can bind to the tetrahedral layers. The octahedral layers take on the structure of either Brucite [Mg(OH)r], ifthe cations are *2 ions like Mg+2 or Fe+2, or Gibbsite [A(OH)3], if the cations are +3 like Al+3. In the brucite structure. all octahedral sites are occupied and all anions are OH-1. ln the Gibbsite structure every 3'd cation site is unoccupied and all anions are OH-I. Mgt2, F e*2, or Al*3 ,{tLrroFjia e tunbfi ftS#) O or OH- Page I of7 ITA-Alfarto10/080/32709r0 Phvllosilicates This gives rise to 2 groups ofsheet silicates: l. The trioctahedral sheet silicates where each O or OH ion is surrounded by 3 divalent cations, like Mg+2 or Fe+2. 2. The dioctahedral sheet silicates where each O or OH ion is surrounded by 2 ffivalent cations, usually Al+3. We can build the structures of the various sheet silicates by starting with the octahedral layers similar to the structures of brucite or gibbsite, as shown below. The trioctahedral phyllosilicates are based on the structure where the octahedral layers are similar to brucite, where Mg+2 occupies the cation position. The dioctahedral phyllosilicates are based on the structure where the octahedral layers are similar to gibbsite, where Al+3 occupies the cation position. Trioctahedral Dioctahedral MBrucite Mg(OH)* Gibbsite Al(OH)l ffi ffi The octahedral sheets in both cases are held tosether by rveak Van der Waals bonds If we start with the brucite and gibbsite structures shown above, and replace 2 of the OH ions with theO, where the Oxygens are now apical Oxygens ofthe tetrahedral sheets, then we get the structure of the serpentine mineral, Lizardite, if the octahedral layer is trioctahedral, containing Mg+2. If the octahedral layer is dioctahedral, containing Al+3, the structure of the clay mineral Kaolinite. is obtained. Trioctahedral wwLizardite MgrSirO5{OH)a Dioctahedral wwKaolinile Al2siros(oH)4 This leads to a tetrahedral - octahedral (T-O) structure, where each T-O layer is bonded to the top (or bottom) of another T-O layer by Van der Waals bonds. Trioctahedral Dioctahedral If 2 more of the OH ions in the octahedral Talc M93SiaOls(0H)2 layer are replaced by O, and these O become the apical Oxygens for another Htetrahedral layer, the this builds the trioctahedral phyllosilicate talc or the dioctahedral pyrophyllite. This becomes a T-O-T layer that can bond to other T-O-T lavers bv weak Van der Waals bonds. H Pyrophyllite AlrSi{Olo(OH)2 Page2 of7 ITA-Alfar1or0/080t2308r00 Phyllosilicates Ifan Al+3 is substituted for every 4th gf4 in the tetrahedral layer, this causes an excess -l charge in each T-O-T layer. To satisfu the charge, K+l or Na*l can be bonded between 2 T-OT sheets in l2-fold coordination. Trioctahedral Phlogopita KMg3AIS{O toi0H), Dioctahedral Muscovite KALAlSrrOro(OHh For the trioctahedral sheet silicates this becomes Phlogopite (Mg-biotite), and for the dioctahedral sheet silicates this becomes Muscovite. This makes a T-O-T - T-O-T layer that, again can bind to another T-O-T - T-O-T layer by weak Van der Waals bonds. It is along these layers ofweak bonding thatthe prominent {001} cleavage in the sheet silicates occurs. Replacing 2 more Si+4 ions with Al+3 ions in the tetrahedral layer results in an excess -2 charge on a T-O-T layer, which is satisfied by replacing the K+l with Ca+2. Trioctahedral C lintonite CaMgrAl"S-5O to(OH), Dioctahedral Margarite CaAlrAlSirOto(OH), This results in the trioctahedral sheet silicate - Clintonite and the dioctahedral sheet silicate Margarite. Because ofthe differences in charge balance between the trioctahedral and dioctahedral sheet silicates, there is little solid solution between the two groups. However, within the trioctahedral sheet silicates there is complete substitution ofFe+2 for Mg+2 and limited substitution of Mn+2 into the octahedral sites. Within the dioctahedral sheet silicates there is limited substitution of Fe+3 for Al+3 in octahedral sites. In addition, F- or Cl- can substitute for (OH)- in the hydroxyl site. As previously discussed, substitution of F-1 stabilizes the mineral to higher pressures and temperatures. Another group of phyllosilicates that is more of mixture of structural types is the chlorite group. Although chlorite is complex in that the amount of Al that can substitute Mg and Si is Page 3 of 7 ITA-Alfar1o0t/080/2308110 Phyllosilicates variable, one way of looking at the chlorite structure is shown below. Chlorite {MgrAl){SirAlPro{O H)t Here, the chlorite structure is depicted as consisting of a brucite-like layer (with some Al) sandwiched between tetrahedral layers that are similar to phlogopite. lMg3Al$irOss(0H)2f ffi IMgrAl(OH)rl+r Another important sheet silicate structure is that of vermiculite. This is similar to the talc strusture, discussed above, with layers of water molecules occurring between each T-O-T layer. Similarly, insertion of layers of water molecules between the T-O-T sheets of pyrophyllite produces the strucfure of smectite clays. The vermiculite and smectite groups are therefore expanding type sheet silicates and as the water is incorporated into the structure the mineral increases its volume. Although we have shown that the octahedral layers fit perfectly between the tetrahedral layers, this is an oversimplification. Ifthe tetrahedral layers were stacked perfectly so that apical oxygens were to occur vertically aligned, then the structure would have hexagonal slmmetry. But, because this is not the case, most of the phyllosilicates are monoclinic. Serpentine Group The serpentine group of minerals has the formula - MgrSirOr(OH)0. Three varieties of serpentine are known. Antigorite and Lizardite are usually massive and fine grained, while Chrisotile is fibrous. As discussed above, the imperfect fit ofthe octahedral layers and the tetrahedral layers causes the crystal structure to have to bend. In Antigorite the bending ofthe sheets is not continuous, but occurs in sets, similar to comrgations, as shown Teirahedral Layet6 here. Octahedrrl Layers Antigorite Page 4 of7 ITA-AlfartoU080/02308120 Phyllosilicates Ghrisotile In Chrisotile, the bending ofthe sheets is more continuous, resulting in continuous tubes that give the mineral it's fibrous habit. The Chrisotile variety is commonly referred to as asbestos. Tetrahedral LaYer Octahedral Layer Occurrence - Serpentine is found as an alteration product ofMg-rich silicates like pyroxene and olivine. It results due to hydration. For example: 2MgrSiO* + 3H2O <=> MgrSirOs(OH)4 + Mg(OH), Olivine water Serpentine Brucite Thus, serpentine is commonly found pseudomorphed after olivines and pyroxenes in altered basic and ultrabasic igneous rocks, like altered peridotites, dunites, and sometimes basalts and gabbros. It is commonly associated with minerals like magnesite (MgCOf, chromite, and magnetite. If the rock is made up almost entirely of serpentine, it is called a serpentinite. Properties - Because the serpentines usually occur either as fine-grained aggregates or fibrous crystals, optical properties are difficult to determine. Most of the time, serpentine can be distinguished by its characteristic pseudomorphing of other crystals like olivines and pyroxenes. In hand specimen it generally tends to have a dark green color with a greasy luster. In thin section it is clear to pale green to pale yellow, but does not show pleochroism, shows a generally low relief compared to minerals like olivine and pyroxene with which it is associated, and show very low order interference colors due to its low birefringence' Talc Talc has the chemical formula - MgrSioOls(OH)2. It is probably best know for its low hardness. Although it has a micaceous structule, it is so easily deformed, that crystals are rarely seen. Occurrence - Like serpentine, talc requires an environment rich in Mg, It is therefore found in low grade metamorphic rocks that originated as ultrabasic to basic igneous rocks- Rocks composed almost entirely oftalc have a greasy feel and are refened to as soapstone. Properties - Talc is most easily distinguished in hand specimen by its low hardness, greasy feel, and association with other Mg-bearing minerals. When crystals are present they show the characteristic micaceous cleavage on {001 }. In thin section, talc is colorless, biaxial negative with a 2V of 0 to 30o. Like other sheet silicates, it shows the well developed {001 } cleavage. Maximum interference colors, consistent with a birefringence of 0.05 is 30 yellow. Muscovite has a higher birefringence and higher 2V, properties which easily distinguish the 2 minerals. Page 5 of7 ITA-Alfarott0/800132803r0 Phyllosilicates Mica Group The micas can be divided into the dioctahedral micas and the trioctahedral micas, as discussed above. Muscovite, Paragonite, and Margarite are the white micas, and represent the trioctahedral group, and Biotite and Clintonite (Xanthophyllite) the black or brown mic4 represents the dioctahedral group. Muscovite and Biotite are the most common micas, but the Lithium- rich, pink mica, Lepidolite, K(Li,Al)rAlSi3Ot0(OH)2 is also common, being found mostly in pegmatites. Muscovite Muscovite, KAl3Si3Ot.(OH)r, and Paragonite, NaAl3Si3Ot'(OH)r, are two potential end members of the solid solution series involving K and Na. But, there is a large miscibility gap between the two end members with Muscovite being between 65%o and, 100% of K-rich end member, and Paragonite showing compositions between about 80o/o and 100% of the Na-rich end member. Occurrence - Muscovite is common constituent of Al-rich medium grade metamorphic rocks where is found in Al-rich schists and contributes to the schistose foliation found in these rocks. Muscovite is also found in siliceous, Al-rich plutonic igneous rocks (muscovite granites), but has not been found as a constituent ofvolcanic rocks. In these rocks it is commonly found in association with alkali feldspar, quartz, and sometimes biotite, garnet, andalusite, sillimanite, or kyanite. Properties - Muscovite is easily identified in hand specimen by its white to sometimes light brownish color and its perfect {001} cleavage. In thin section, the {001} cleavage is easily seen and it's high birefringence is exhibited by the large change in reliefon rotation ofthe stage and it's 2nd to 4th order interference colors. It is clear and shows no pleochroism (which distinguishes it from Biotite), and it is biaxial negative with a 2V between 28 and 50o. One of the most diagnostic properties of the micas, including muscovite, is the mottled or birds-eye extinction exhibited by these minerals. Biotile Biotite is a solid solution between the end members Phlogopite KMgrAlSirOrg(OH)2 and Annite KFerAlSi3Ol'(OfD2'although pure Annite does not occur in nature. In addition, small amounts of N4 Rb, Cs, and Ba may substitute for K, and like in other minerals, F can substitute for OH and increase the stability of Biotite to higher temperatures and pressures. Occurrence - Nearly pure phlogopite is found in hydrous ultrabasic rocks like kimberlite, and is also found in metamorphosed dolomites. Biotite, with more Fe-rich compositions is common in dacitic, rhyolitic, and trachyic volcanic rocks, granitic plutonic rocks, and a wide variety of metamorphic rocks. In metamorphic rocks, biotite usually shows a preferred orientation with its {001} forms parallel to the schistose foliation. Properties - In hand specimen, Biotite is brown to black and shows the perfect {001} micaceous cleavage. In thin section, it shows the perfect cleavage and mottled extinction Page 6 of 7 ITA-Alfartot/080/02308140 Phvllosilicates typical of all micas. It's most characteristic property is its pleochroism, showing yellow to brown to green colors. Homblende shows similar pleochroic colors, but is distinguished from biotite by the differences in cleavage of the 2 minerals. Biotite is biaxial negative with a low 2V of0o to 25o. Chlorite Group As discussed above, the Chlorite group has a structure that consists of phlogopite T-O-T layers sandwiching brucitelike octahedral layer. There is substantial substitution of Mg for Fe, and Al can substitute for (Mg, Fe) in both the octahedral sites, as well as for Si in the tetrahedral sites. Thus, chlorite can have a rather complicated formula - (Mg,Fe,A1)r(Si,Al)4O10(OH)6. Occurrence- Chlorite is a common mineral in low grade metamorphic rocks, where it occurs in association with minerals like actinolite, epidote, and biotite. It also forms as an alteration product of pyroxenes, amphiboles, biotite, and gamet in igneous as well a metamorphic rocks. Properties - In hand specimen, chlorite is recognized by its green color, micaceous habit and cleavage, and association with other minerals like actinolite and epidote. In thin section, Chlorite shows low relief and low birefringence, with a characteristic midnight blue to black anomalous interference color. It shows some pleochroism in the range of green to pale yellow. It is easily distinguished from biotite by its lower reliefand anomalous interference color. Examples of questions on this material that could be asked on an exam (note that properties that distinguish different minerals will be included in the laboratory exam) l. What is the difference between the dioctahedral and trioctahedral sheet silicates? 2. What is the difference between antigorite and chrysotile ? 3. State whether each of the following minerals would be most commonly found in igneous rocks, metamorphic rocks, or both igneous and metamorphic rocks: (a) Chlorite, (b) biotite, (c) muscovite, (d) talc, (e) serpentine, Retum to EENS 2110 Pase PageT of7 ITA-Alfarlot/080t02308150