Rock Crystal is the name given to all clear colorless quartz. Rock crystal, a transparent variety of the silica mineral quartz is valued for its clarity and total lack of color or flaws. It is also known as Alaska diamond or mountain crystal. Rock crystal does not contain enough trace minerals to affect its coloration, so it appears clear.
When molten rock, or magma, begins to cool beneath the Earth’s surface the various minerals found within the magma begin to crystallize. If silicon dioxide cools to a temperature below 573 degrees Celsius it will begin to crystallize into quartz or rock crystal. Depending on the concentration of other minerals within the silicon dioxide, different types of quartz will form. Rock crystal is only one of several quartz varieties.
Rock crystal’s name derives from the Greek term “krustallos” meaning “ice” and it is the sister gemstone to colorful varieties of quartz, such as amethyst and citrine.
Many people prefer uncut clusters of rock crystal. The best rock crystal sources are in the famous Hot Springs area of Arkansas, USA; Cumberland, England; St. Gotthard, Switzerland; Brazil and Madagascar. Large individual crystals of quartz have been found in Brazil, the largest weighs over 44 tons.
Rock crystal is widely used as a popular ornamental stone and is also used as a gemstone. The most common use for rock crystal is in ornamental carvings.
Rock crystal is an alternate and traditional birthstone for the month of April.