A formal appraisal could be made by a gemologist, or a respected mineral dealer. You could also see items of a similar nature for sale on ebay, and somewhat determine from that the value of your specimen.
Rainbow quartz is a term used for describeing two states of quartz crystal. One state, is a quartz crystal that has been fractured internally. The refraction of light through the crystal, produces a rainbow color spectrum. The second state, are quartz crystals that have been coated in titanium. The coating gives the surface of the quartz a rainbow effect.
Not much. Quartz is almost completely insoluble in water.
There are many factories make quartz crystals, from crystal bar to crystal blank. And there are many kinds of products called quartz crystal, such as QCM sensor, people also call it crystal, but it's not a simple crystal but with gold or silver or chrome and other materials plated, with metalized electrode on it.
Quartz crystals typically grow hydrothermally, in hot, pressurized, silical solutions.
Quartz and feldspars are the most common minerals found in continental crustal rocks.
Amethyst is a variety of crystal quartz.
Pure quartz is a homomogeneous crystal.
Quartz.
There are several differences, the primary one being that on the Mohs hardness scale, diamond is 10, quartz is 8. Quartz crystal is very hard, but diamond is harder.
quartz crystal
Rainbow quartz is a term used for describeing two states of quartz crystal. One state, is a quartz crystal that has been fractured internally. The refraction of light through the crystal, produces a rainbow color spectrum. The second state, are quartz crystals that have been coated in titanium. The coating gives the surface of the quartz a rainbow effect.
Piezo-electric Effect
Not much. Quartz is almost completely insoluble in water.
A Quartz crystal is worth about 20$-35$ an ounce.
mm
A small quartz crystal can grow about 1mm a week assuming it is in a stable matrix.
Maybe lechatelierite? Or crystal (as in quartz glass)?