APOPHYLLITE-(KF)

HISTORY, NAME, LOCALITIES: The apophyllite mineral group was recognized in the early 1800s and first thought to be a single mineral.  Its name stems from the Greek apo, meaning “detached” or “off,” and phyllon, or “leaf,” and translates roughly as “to leaf apart,” a reference to its tendency to separate along cleavage planes into thin sheets when heated.  Its name was later changed to “fluorapophyllite” and to its current name to indicate that it is the potassium-fluorine-rich member of the apophyllite group.  Collecting localities are located in India, Germany, Brazil, Japan, Mexico, and the United States (New Jersey, Pennsylvania, Arizona).

MINERALOGY, PROPERTIES, OCCURRENCE: Apophyllite-(KF) [basic hydrous potassium calcium fluorosilicate, KCa₄Si₈O₂₀(F,OH)·8H₂O] pronounced ah-PAH-fill-ite (kay-eff), is a member of both the apophyllite group and the phyllosilicate subclass of the silicate minerals.  It has a Mohs hardness of 4.5-5.0, perfect cleavage in one direction, and a specific gravity of 2.3-2.4.  It crystallizes in the tetragonal system as well-formed cube-like or tabular crystals with either flat or pyramidal terminations.  It is transparent to translucent and colors range from colorless and white to pale green, yellow, and pink.  Apophyllite is a secondary mineral that forms in the vesicular cavities of basaltic rocks in association with zeolite minerals.

METAPHYSICAL PROPERITES, LORE, USES: According to modern metaphysical beliefs, apophyllite-(KF) helps to reduce fears and feelings of apprehension and aid in establishing control of emotions and situations.  Apophyllite has no technological uses.

COLLECTORS’ INFORMATION: Apophyllite is collected for its bright luster, well-developed crystals, and range of attractive, pastel colors.