3.5 x 2.3 x 1.8 cm. Cronstedtite is a rare iron silicate of the serpentine group. This very rich and showy little specimen is festooned with lustrous, black, trigonal crystals to 3 mm on a 3-dimensional crust of matrix. It is a rare occurrence to have such a rich coverage of cronstedtite, and this specimen displays very well. This is a classic rarity from the famous Herja Mine of Romania.