u/bestgemsandminerals

Aquamarine, Emerald, Garnet, Kunzite, brookite, Topaz, alkali beryl, wernerite

Just lovely crystals

This specimen is a fascinating example of Alkali Beryl (often referred to locally or in older texts as Vorobyevite or Rosterite). Found in the remote Deo Darrah ("Valley of Jin") and Khash districts of Badakhshan, Afghanistan, these crystals are prized by collectors for their unique chemistry and unusual shapes.

What Makes it "Alkali"?

Standard beryl (like emerald or aquamarine) is a beryllium aluminum silicate. However, the geology of Badakhshan is rich in alkali metals.

• The Chemistry: In these specific crystals, elements like Sodium (Na), Lithium (Li), and Cesium (Cs) crowd into the "channels" of the crystal structure.

• The Result: This high concentration of alkalis changes the physical appearance of the beryl, often turning it from the typical long "pencil" shape into flat, plate-like (tabular) crystals.

Kunar, Afghanistan