Chemical Formula (Quartz) SiO2
Crystal Structure Trigonal
Mohs’ Hardness 7
Main Sources Brazil, India, Australia, Russia, United States (California)

Associated Birth Month
Cancer (Jun 21 – Jul 22)


Chalcedony is the cryptocrystalline form of quartz that forms in a wide variety of shapes and colors. There are many different forms of chalcedony, but they are generally referred to by subcategories such as agate, fire agate, onyx, sardonyx, chrysoprase, jasper, carnelian, and bloodstone. Typically only the blue, and in many cases lavender or periwinkle blue, shades of chalcedony are referred to without another such designation.

The name chalcedony is believed to have been derived from the ancient port of Klakedon in Asia Minor (modern Turkey), where some of the earliest deposits are thought to have been unearthed.

Metaphysical Properties

Chalcedony is believed to sooth depression, dispel irritability and bring joy and happiness. It is suppose to help with mental clarity by supporting balance and reducing negativity. Chalcedony is also supposed to help with ailments such as melancholy, fever, eye-problems, and gallstones. Maternal feelings and instincts are believed to be heightened with chalcedony.