The mineral selenite is a form of gypsum that exhibits an obvious crystalline structure. Gypsum is a very soft mineral made up of calcium sulphate dihydrate (dihydrate meaning two molecules of water). Dissolved calcium sulphate causes permanent hardness in water.
Gypsum which is widely available is used as a fertiliser, for blackboard chalk and is the main constituent of plaster and plaster of Paris. When the mineral crystallises it becomes known as selenite, satin spar, desert rose or gypsum flower. These four varieties of crystalline gypsum differ because of the way they crystallise.
Satin spar features long fibrous crystals that are white and opaque. It's well known for its silky or pearlesque lustre and is often incorrectly labelled as selenite. Selenite forms clear colourless crystals and like all varieties of gypsum is very soft. In fact selenite is so soft it can easily be scratched with a fingernail. Selenite crystals are some of the largest crystal formations in the world.
Desert rose forms distinctive rosette shaped clusters with flat petal-like crystal formations whilst gypsum flowers feature curved shaped crystals that radiate outwards from a centre point. This mineral which can resemble a flower grows in caves and forms in a similar way to stalactites and stalagmites.
This fine grade selenite mineral from our collection has a distinctive vitreous to pearly lustre and is completely transparent. On the front its crystal faces can be seen and felt whereas the back is flat and exceptionally smooth. A beautiful piece that needs to be supported or placed on a small stand for it to remain upright.
The name selenite originates from the Greek words for 'moon' and 'stone' or 'stone of the moon'. In Greek mythology Selene was the goddess of the moon.