Rayite, a monoclinic mineral containing Lead-Silver-Thallium-Antimony, was found during microscopic and electron microprobe study of specimens from the complex, polymetallic sulphide-native metal sulpho-salt paragenesis of Rajpura-Dariba, Rajasthan, India. It is named after Dr. Santosh K. Ray of President College, Calcutta, India. It bears a striking resemblance to owyheeite in terms of its Lead/(Silver,Thallium)/Antimony ratio, yet its structural affinity lies with Semseyite. The average composition is Lead-47.06, Copper-0.03, Silver-4.54, Thallium-2.04, Antimony-27.42, Sulphur-19.59 by wt.%
Rayite, a monoclinic mineral containing Lead-Silver-Thallium-Antimony, was found during microscopic and electron microprobe study of specimens from the complex, polymetallic sulphide-native metal sulpho-salt paragenesis of Rajpura-Dariba, Rajasthan, India. It is named after Dr. Santosh K. Ray of President College, Calcutta, India. It bears a striking resemblance to owyheeite in terms of its Lead/(Silver,Thallium)/Antimony ratio, yet its structural affinity lies with Semseyite. The average composition is Lead-47.06, Copper-0.03, Silver-4.54, Thallium-2.04, Antimony-27.42, Sulphur-19.59 by wt.% (total 100.68) suggesting an ideal formula of Pb8Sb8S21, where Ag > Tl. Meneghinite, Owyheeite, and Galena are related minerals.
==Occurrence== It was found in the ores of precambrian polymetallic massive-sulfide deposit interbedded with kyanite-graphite schists, diopside-bearing calc-silicates, and meta-cherts in Rajpura-Dariba deposit, Udaipur Division, Udaipur District, Dariba Mine, Rajasthan, India. It is observed in patches, measuring up to 0.5 mm, reaching a maximum dimension of about 30 μm.
Discovered by embedding cosine similarity (sentence-transformers MiniLM, 384-dim).