Abstract: Quanjiao County，Arihui prov .is .the only place in China where
occurs recoverable sepiolite and its outcrop.The results of the sepiolite
identified by using g means are presented and compared with those of
the sepiolite of other areas in the world.
The sample from the outcrop is an asbestiform fibrous mineral.It
has the first grade interference colors，and is biaxial pos.with 2V≌61°，
Ng=1 .5292，Nm=1.5214，Np=1.5186，max.birefringence p.010, and is
Ierigth pos. with parall.extinction.X-ray powder diffraction shows that
the specimen is well crystallized se,piolite.IR spectra exhibit I small but
distinct band at 3685 cm^-1，in addn.to 2 broad bands at 3560 and 3410
cm"t, with a shoulder at 3250 cm^-1， In the region 400-1300 cm^-1, the
samples exhibit I broad band at 1200-12 cm^-1;1, 3 very large bands near
1070, 1020 arid 975 cm^-1，3 broad bands at 780, 690(shoulder at 723)，
and 640 cm'1, and 1 large broad band at 465 (shoulder at 425) cm^-1.DTA
curves have a double endothermic peak at 125-150 C and 805-818 C，and
eridothe.rm-exotherm inversion at 740.℃·A them·anal，given is SiO₂ 52.4,MgO 22.01,H₂O(+)12.42,H₂O(-)6.88 and SiO₂/MgO 1.59, and.sug-
Bests the mol .formula H₆Mg₃Si₁₂O₃₀(OH)₁₀·6H₂O，The electron micro-
graph shows that the sample examined is a pure sepiolite.
The physical aad. chum.prop.，crystallized structure，origin and
main use's of sepiolite are also discussed.

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