Apophyllite, Meaning, Properties, and Facts

What is apophyllite

Apophyllite is the name for a small group of sheet silicate minerals, and most specimens are fluorapophyllite-(K), a potassium calcium silicate with fluorine and eight water molecules in each formula unit. It is not a zeolite, though it grows with them. The name comes from the Greek apo, away, and phyllon, leaf, because it flakes apart when heated, as Mindat's apophyllite group page notes.

Apophyllite properties

Apophyllite properties include one perfect cleavage across the crystal and a pearly shine on that surface, which earned it the old name fish-eye stone. It is soft for a clear crystal, 4.5 to 5 on the Mohs scale, so quartz scratches it. Crystal data is on Wikipedia's apophyllite page.

Where apophyllite is found

Apophyllite is found in gas cavities in basalt lava flows, where hot groundwater deposited it along with zeolites and calcite. The best known source is the Deccan Traps of western India, flood basalts about 66 million years old, where quarries near Pune, Nashik and Jalgaon in Maharashtra yield clear and green crystals in quantity. Other sources include Brazil, the Harz Mountains of Germany and the basalts of New Jersey.

Apophyllite crystal forms

Apophyllite crystal forms are four-sided: blocky prisms with flat tops, and steep pyramids that look cut but are natural, though many have a sawn base. Most crystals are colorless or white, and green apophyllite from the Pune area is the most sought after. Peach stilbite and white scolecite needles often grow in the same cavities.

How to tell if apophyllite is real

To tell if apophyllite is real, look at the shape and the shine. Apophyllite crystals are square in cross section, while quartz is six-sided and harder. The flat top of a blocky crystal shows a pearly, almost mother-of-pearl shine. Calcite, a common neighbor, is softer and forms rhombs or pointed dogtooth crystals. Fakes are rare because natural apophyllite is plentiful, but check clusters for glue.

Apophyllite care: water and sun

Apophyllite care starts with water: a quick rinse in cool water is fine, but do not soak it, especially clusters on matrix, and never use hot water or ultrasonic cleaners. Display light is not a known problem, but keep it away from heat, which drives out the water in its structure and leaves the crystal white and flaky. Pick it up by the matrix, since corners chip easily. See water safe crystals.

Apophyllite price and value

Apophyllite price and value are friendly for small clusters and points, because Indian quarries produce so much of it. Prices climb for large, sharp, transparent crystals, green color, undamaged faces and attractive pairings with stilbite on matrix.

Apophyllite meaning and benefits

Apophyllite meaning in crystal lore is clarity and spiritual connection, and the benefits people claim for it include calm and sharper intuition. That is belief, not chemistry. The science is plenty on its own: a crystal that grew from hot water inside a lava bubble and still holds water in its structure.

Apophyllite for sale

Apophyllite for sale at geoslut arrives in drops. Each piece is one of one, photographed in daylight and labeled with its locality, and the list hears first.

Apophyllite FAQ

Is apophyllite water safe?

Apophyllite is water safe for a quick rinse in cool water. Do not soak it or use hot water.

Is apophyllite a zeolite?

Apophyllite is not a zeolite, though it grows in the same basalt cavities as zeolites such as stilbite and scolecite.

Why is apophyllite square?

Apophyllite is square because it crystallizes in the tetragonal system, which builds four-sided prisms and pyramids.

How hard is apophyllite?

Apophyllite is moderately hard at 4.5 to 5 on the Mohs scale, so quartz and steel scratch it.

Sources

• Apophyllite Group, Mindat
• Apophyllite, Wikipedia
• Apophyllite Mineral Data, Webmineral