What is Druzy and how does it form?


Staff member
Jun 3, 2020
The word Druse (also known as Drusy or Druzy), refers to an aggregate mass of small crystals (“crystal druse”) usually formed by many different minerals. The fluid composition defines the species and shapes of crystals. Crystal size varies with fluid temperature and pressure. A druzy is sets of tiny crystals of minerals that form on the surface of another stone. There are many types of druzy with particular characteristics, such as crystal size, luster and color.

Physical appearance of Druzy
Quartz is one of the most common druzy types because of its abundance. The overall appearance of druzy usually resembles that of sugar, regardless of the minerals. The tiny crystals are considered beautiful because, like large gemstones, they glitter and catch rays of light. The usual minerals like Dolomite, Malachite, and Calcite are also found in Druzy Crystals.

Geological formation of Druzy
The Druzy forms when mineral fluids evaporate on a rock's surface leaving minerals to form crystals on top of the rock. They can occur in any color depending on the minerals. Most of them form as cavity lining in geodes. The botryoidal agate mass of the geodes are irregular, lumpy like a cluster of grapes. As a result, typically the surface area for cutting a cab is small. Large stones are less common. Many cutters keep a border of plain agate around the druzy covered area of the cab to produce larger cabs.

The alignment of crystals in a Druzy is mostly random making them glitter like a fistful of diamonds. However, sometimes they have uniform alignment like jewelry and the light flashes back from their surface. The crystal Druses other than Quartz are rare. The coatings and dyes are used to improve the less attractive colors into attractive shades.


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