The name "drusy" is derived from the German word for geode, which is "druse."
You may see drusy quartz spelled as druse, druzy, or drusies. Either way, it is all the same gem. The simplest definition for drusy quartz is that it is a rock covered in tiny crystals. Tiny quartz crystals form inside geodes, in large pockets of mineral deposits, or on the surface of other stones, such as agates or chalcedony.
Here is a more "scientific" or "geological" explanation. "When ground water carrying dissolved silica is forced into a porous area of the rock, rapid cooling often occurs, causing the formation of tiny crystals on the surfaces or in cavities of the rock. The clear crystals often form on top of previously deposited minerals."
Druse gemstone cabochons are natural stones, having a quartz base and a thin layer of crystalline quartz on the surface that sparkles. You can find natural colored drusies in turquoise blue, green, pink, mauve, lavender, black, white, grey, dark brown, deep red, and rust colored red. Some of the coloring in the natural colored drusies comes from the crystals themselves, and in others, the color comes from the underlying gemstone, such as agate or chalcedony, and the transparent druzy crystals "convey" that gem color to your eye.
Vapor deposition is the name of the treatment when metals like titanium, gold or platinum are used to improve the color of a dull druzy or impart the distinctive color of the metal. Titanium metal coating will produce spectacular shades of bight, dark blue or an iridescent white, that are permanent.
***The coating on a drusy is thin, so the drusy needs to be treated with care. If you scratch them hardly, the base gemstone will show through.
Care for Drusy Quartz Cabochons
Druzy gemstones are a 7 on the Moh's scale of hardness. That means they are fairly hard and thus durable in jewelry. Of course, they are more fragile than their smooth, domed surface, counterparts and some care must be taken when setting, cleaning, and wearing these stones.
Over and over I read that druse crystal cabochons are best set in pendants or earrings, and are not really suitable for rings and bracelets. That is because you can scratch the coating off a coated druse, or break a crystal if you bang the cabochon too hard. Custom designed jewelry with druse cabochons are best used for dress up, rather than every day wear.
As with most gemstones, drusy should be kept away from chemicals like solvents and acids and from exposure to heat as this can cause damage or permanent changes to its appearance.
***For the Jeweler: To protect the beautiful finish on these gemstones against inadvertent abrasion, we recommend covering the surface with a clear plastic while you position and set them into your bezel. Place a soft cloth between the stone and the work surface to protect the underside of the stone as well.
Please remember that the metallic coatings are not thick, so NEVER machine-buff the surface of coated druzy.
This information has come from various sources online. A couple of the sources are:
Bernadine Fine Art Jewelry's blog and the blog of the Examiner.
***If you would like to see the selection of druzy quartz cabochons that TigerBeadStore.com carries, please go to this link.