The following is a list of Geniculate gems and minerals listed in our database. Click the pictures to get full data, click the X to remove the gem from the list.
Cassiterite: Cassiterite may form as short or slender prismatic, or bipyramidal, elbow-shaped crystals. It has a crystal surface reflecting light as in a mirror. They may occur as massive, granular, botryoidal, and reniform. When found in granular, banded, fibrous masses, it looks like wood. When found in groups of large bright crystals, it is usually called "diamond tin." A red variety cut for collectors is k (read full)
Rutile: Rutile with anatase and brookite is a trimorph of titanium oxide in the Rutile group.
It forms characteristic slender prismatic striated lengthways, variably terminated and often geniculate twinned crystals of the tetragonal system. Elbow- and heart-shaped (geniculated) twin crystals are common.
It is hard, heavy, fragile, with perfect cleavage.
It has a metallic to adamantine lustre an (read full)
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Spessartine is the manganese-aluminum variety of Garnet, belonging to its sub-group of aluminum garnets. Garnets are a group of silicat
Agate Chalcedony differs from other Chalcedony in that it often has distinct banding. In fact some slices of Agate may appear to have 
Rose quartz is a usually cloudy, translucent, delicate pale pink, deep pink, rose-red to quasi-white and often veined variety of Quartz
Anglesite is a very soft gem just slightly harder than gold and silver and as such it does not hold facets well/cut easily.
Because of