Cassiterite

Unknown Owner

We all know that Cassiterite is the main ore of tin and that good crystals are uncommon, even within famous tin mining regions. This single crystal is a colossus, it is simply enormous and you will struggle to find another so large and in such good shape as this, from anywhere. It is from the remote Iul'tin mine in the far northeast of Russia and was probably mined many decades ago. Off matrix, this square (or rectangular)-sectioned dark brown resinous prismatic crystal is nicely terminated with a pyramid topped with a slight flat pinacoid face. It is a staggering 6.7 cm tall by 5 cm wide, and weighs a hefty 0.5 kg. All prism sides are present to a degree: two complete at the top and two partially and the pyramid faces are similarly complete, but it looks stunning. The main front prism face presents a 'U'-shaped cavity, where the internal growth lines can be seen, and where another large crystal must have once been present. Minor rosettes of Muscovite mica form inclusions in the back of the crystal. A world-class Cassiterite crystal.