Here we have a superb cluster of mirror bright, intergrown, single and twinned Cassiterite crystals measuring 2,8 cm across with dark black-brown colour. This crystals are exceedingly well defined, sharp edged and superb striated. Almost opaque due to the dark colour but with clearly visible brown eternal reflections with backlit. This is a super thing with splendend aesthetics and only minor imperfection. A stunning mini from an old time Czech locality and extremely hard to come by nowadays.