Mohs hardness: 7
Refractive index: 1.544-1.553
Critical angle: 40°
Specific gravity: 2.63-2.65
Fracture: Conchoidal, brittle.
Dispersion: Medium (.013)
Heat sensitivity: Low
Pleochroism: Amethyst: very weak (purple to grayish purple); Natural citrine: weak (yellow to light-yellow); Prasiolite: very weak (light-green to paler green); Rock crystal: colorless, no dichroism; Rose quartz: weak (pink to paler pink); Natural dark smoky: definite (brown to reddish-brown).
Birefringence (double refraction): Weak (.009)
Crystal structure: Hexagonal
General Gemstone Details
Quartz is a power stone, and has been called as well as considered world wide as the "Universal Crystal". It is the most recognized type of crystal, and what many people envision when the thought of "crystal" comes to mind. In fact there are many different types of Quartz, in quite a variety of colors.
"Rock Crystal" Encompasses a large family of stones and crystals, all of which are made up primarily of silicon dioxide, one of the most common and most important substances in the world. Crystals of pure Quartz, generally six-sided, can be found in all shades and colors. Quartz crystals grow singularly or in groups and take on different shapes according to the temperature at the time of their formation. Quartz crystals can also contain other minerals "frozen" within, as in Rutilated Quartz. Quartz can be formed of microscopic crystals and take on entirely different appearances and qualities.
Quartz can be a bit of a confusing stone, as it encompasses a great many varieties that often are thought to be gemstones on their own, but are in fact another type of quartz. As well, within the quartz family there are other stones, which have their own little "families" as well. Here is a breakdown of the most common quartz varieties:
Mohs Hardness of 7 with a trigonal crystal structure.
The name "quartz" comes from the Greek derivative krustallos, meaning ice, as it was thought that quartz was actually ice formed by the Gods. Since the Middle Ages, crystal balls made of rock crystal have been used to predict the future.
Visual clarity normally isn't as important to a quartz crystal's energetic quality and ability to amplify subtle energies around it. Quartz enhances energy by absorbing, storing, balancing, amplifying, focusing and transmitting the energy...it channels universal energy as well, and is quite successful for energizing other crystals.
Quartz crystals can raise energy to the highest possible level, it enhances thoughts, as they are a form of energy, and it is extremely beneficial for manifesting, healing, meditation, protection and channeling. Containing every possible color, Clear Quartz wor