Document KaryzLdGJ7ybnbo8ZL9peEr0

FILE NAME: Johnson & Johnson (JAJ) DATE: 1971 Oct 21 DOC#: JAJ053 DOCUMENT DESCRIPTION: Report - Examination of Talc Samples for Windsor Mineral Company  {. r y f Report to: Windsor M ineral Company Windsor, Vermont 0S089 9 Technical Report MA-2401 # EXAMINATION OF TALC SAMPLES * FOR WINDSOR MINERAL COMPANY . Submitted by: V." \\ W elter C. McCrone A ssociates, Sic. 493 East 3 Ist Street * Chicago, Illinois 60616 Geue R. Gretger Principal Investigator b n M. Stewart . -Manager, Electron - Optics Group of jc o p ie s 21 October 1971 i Walter C. McCrone Associates, Inc. P ro lteM Docum ant-Subfcetlo Protactiv* Ontor EXHIBIT -4* JNJAZS5JI000SH7 4 Technical Report MA-2401 > ' . T ! / . ' ' . . . . . . . . . ; ex a m inatio n o f t a l c sa m p l e s FOR WINDSOR MINERAL COMPANY . . ' . i Summary A Three talc sam ples, Identified a s 2676-55A , 2676-5SB, and 2676-55C, have, been exam ined for the Windsor M ineral Company with particular empha- v ate being placed on the fiber content of the m aterials, particularly fib ers of the asbestiforra m inerals. Of the three sam ples, A and C were found to contain several fibers e of unknown m ineralogical types, none of which yielded electron diffraction patterns which would perm it their identification. Several of these fib ers ap- em * .. . peared m orphologically sim ilar to eb rysotfle, but no positive identification was possible. x Sample C showed the thinnest plates of talc and on th is b asis is Judged v. ' to be the b est talc of the three sam ples. I# W alter C . M cCrone Associates. Inc. Protected Document-Subjoct to Protective Ord.r JNJAZWJM000686S jjirtfn 4L K^a^f EXAMINATION OF TALC SAMPLES FOR Win d so r m in e r a l c o m a pn y Introduction Three samples of talc, identified as 2676-55A, 2676-55B, and 2676-55C * w ere submitted by the Windsor Mineral Company, Windsor, Vermont, for eixamination by electron microscopy, and electron.diffxaction.tecbiiigues._lhformation was sought on the fiber content of the three samples, in particular the presence of asbesttform mineral fibers. K was further requested that we compare samples A and B with sample C. For this reason, sample C will be described first. Results of the Examination Sample 2676-55 C . This sample has a very clean appearance with extremely thin plates of talc and very few pieces of rolled talc, hi our examination of this sample we observed two fine fib ers, neither of which could be positively identified since they did not yield diffraction patterns but one of which did have a mor phology sim ilar to chrysotile. It should be pointed out, however, that we observed sim ilar morphology in several m inerals. No amphibole particles were observed. The plate-size range in the portion of the sample analyzed in the transm ission electron microscope is approximately 1-3 iim. -2- Walter C. McCrone Associates, Inc. Protected Document-Subject to Protective Order JNJAZ55_OO0OO6969 >1 Sample 2676-55A -------- -- - ' ' to this sample, the talc plates appeared to be thicker, and there Is a slightly higher percentage of rolled talc plates. We found four fibers, three i f which could be classe d-as-suspireiron the basis of their morphology, but none of these fibers could be positively identified. Of the three suspect ffibers, one has a limited sim ilarity and two have substantial sim ilarity to flie morphology of chrysotile, hut they could not be identified as this mineral letroh diffraction patterns from them. Again we detected no amphiboles although there is slightly more extraneous material than la sample C. Sample 2676-55B * Thfe sample appeared very clean, containing no fine fibers of any type, . few er fine talc particles and no amphiboles. There is very little extraneous m aterial present, and only on one occasion did we find any of the normal de composition products of chlorite o r carbonates. The talc plates are not quite as thin as those in sample C hut are thinner than those in sample A. Observations Despite the presence of the two fine fibers in C, this sample appears to be the best example of talc since it occurs as the thinnest plates. We would place sample B as next best on the b asis of plate thickness and sample cleanliness. The possibility that the suspect fibers found in samples A and B originate from some external source of contamination cannot bo precluded. Walter C. McCrohb Associates, Inc. Protected Dwwnnt^hiect Protective Order JNJAZ56_0Q00D597D If ' A The fact that these occurred as isolated fibers would tend to indicate external * rather titan internal contamination of the source m aterial; internal contamina tion would, in general, tend to yield fibrous bundles or aggregates, and it is unlikely that isolated fibers o f the dim ensions which we are observing, approxim ately 20 nm in diam eter, would occur In a natural talc body. * Of * -4- Walter C. McCrone Associates, Inc. Protct l Docum ent-Subjtctto Protective Order . JNJAZ68_000005871