Siderite, Ilvaite
Bor Pit (Boron Pit; Bor Quarry), Dal'negorsk B deposit, Dal'negorsk (Dalnegorsk; Tetyukhe; Tjetjuche; Tetjuche), Primorskiy Kray, Far-Eastern Region, Russia
Cabinet, 10.2 x 7.4 x 6.8 cm
This is a rare pseudomorph specimen from Dal'negorsk. What you have is a cluster of huge, sharp ilvaites that have been completely (it appears) replaced by tan-colored siderite. There are two main clusters of tightly-intergrown crystals. Their faces and terminations are sharply preserved. The fractures you see are natural, having occurred probably due to dessication in the pocket.