Drusy or druzy refers to the fine crystal coating that can commonly be found in various gemstones and jewelry pieces.  Geologically, the term ‘druse” is used when there are fine crystals that cover certain rocks or form at the core or near the veins.  When these crystal-enveloped rocks are seen, they are often referred to as being drused with crystals.  From the term “druse”, any rock coated with fine crystals or jewelry piece that resemble the same is called druzy or drusy.

The fine layer of crystals that form in various rocks are secondary to years of exposure to various natural elements like gases that get trapped within them.  With these gases interacting with other minerals, the rocks will then solidify over several years or decades and form tiny crystals on the surface or at its core.  With the variety of minerals that may interact with gases and rocks, there are also various colors that can be drused into the rocks and become jewelry and gemstones later.

Drusy quartz are said to be the most commonly found crystal-coated stones.  These rock or stone pieces are formed with the help of silica and water.  With the mineral’s natural tendency to react with other substances, crystal quartz is then formed from the inside of rocks or more commonly as coating on the outside.  Other minerals may also be used to react with the crystal formation in drused rocks.  A common example is titanium-based drusy or drused jewelry.  In this particular case, titanium fumes are forced into the drused crystal rock formation to form the desired titanium drusy jewelry or gemstones.  The use of titanium fumes is said to help enhance the color of the crystals which is very helpful when it comes to making jewelry pieces.  The drusy gemstone’s color may also depend on the rock color but common mineral infusions result to drusy rocks with a wide color range.  Aside from quartz and titanium, other gemstones and minerals may also be used to form drusy rocks including calcite and garnet among many others.