Chalcedony Quartz is a type of quartz that is composed of several different minerals, including ONYX (4 letters), Sard (4 letters), SILICA (6 letters), AGATE (5 letters), JASPER (6 letters), CARNELIAN (9 letters), AGATES (6 letters), and OPAL (4 letters). It is known for its hardness and durability, and is often used in jewelry and other decorative items. It is also used in the construction of buildings and monuments due to its strength and beauty.