Pretty specimen of peach colored thompsonite crystals in basalt (?) matrix from the Nizhyaya River, Tunguska, Siberia, Russia. A nice cavity with all the interior crystals intact and undamaged. The perimeter of the specimen is cleaved off thompsonite showing the radiating structure. A rare specimen from a rare locality. Measures 5 x 4 x 2.75 inches ( 12.7 x 10.1 x 7 cm).