Apatite : The yummiest of all blue gems

Apatite

Mind blowing blue Apatite

Apatite, a stone seldom found in jewelry stores and virtually unknown to the general public, is beloved by collectors for its many different colors and forms. Only with the recent availability of the neon blue-green variety from Madagascar, has its jewelry use increased. Care for this stone is similar to that given opals, it is heat and shock sensitive, so steamers and ultrasonic cleaners must be avoided.

Neon Green Apatite

Apatite in my opinion is one of the hardest gems to photograph.  I am convinced that digital cameras just can't comprehend the depth of blue in these gems. I often have to take dozens to pictures just to get one that looks even half way good.

Neon Blue Apatite

Because of it's heat and shock sensitivity Apatite is one of the few gems on the market today that has absolutely no heat treatment or chemical enhancements to improve the look of the gem.

An interesting thing about the name Apatite is that apatite is the mineral that makes up the teeth in all vertebrate animals as well as their bones. The name Apatite comes from a Greek word meaning to deceive.  This is due to it's similarity to other more valuable minerals such as olivine, peridot and beryl.

Apatite is actually three different minerals depending on the predominance of fluorine, chlorine or the hydroxyl group. These ions can be freely substituted in the crystal lattice and all three are usually present in every specimen. However some specimens can be made up of nearly 100% of just one of these minerals. These minerals are Fluorapatite, Chlorapatite and Hydroxylapatite. The three are usually considered together due to the difficulty in distinguishing them in hand samples using ordinary methods.

Apatite is widely distributed in all rock types; igneous, sedimentary and metamorphic.  But mostly usually just small disseminated grains or cryptocrystalline fragments. Large well-formed crystals can be found in certain metamorphic rocks.

Apatite Crystals

Very gemmy crystals of Apatite can be cut as gems but the softness of Apatite prevents wide distribution or acceptance of Apatite as a gemstone.

PHYSICAL CHARACTERISTICS:

• Class: Phosphates
• Group: Apatit
• Uses: as a source of phosphorous to be used in fertilizer, rarely as a gemstone and as a mineral specimen.
• Color:  typically green but also yellow, blue, reddish brown and purple.
• Luster: vitreous to greasy and gumdrop.
• Transparency: Crystals are transparent to translucent.
• Crystal System:  hexagonal; 6/m
• Crystal Habits: include the typical hexagonal prism with the hexagonal pyramid or a pinacoid or both as a termination.
• Cleavage: indistinct in one basal direction.
• Fracture is conchoidal.
• Hardness is 5.
• Specific Gravity: approximately 3.1 - 3.2 (average for translucent minerals)
• Streak is white.
• Associated Minerals are hornblende, micas, nepheline and calcite.
• Other Characteristics: An unusual "partially dissolved" looks like sucked on hard candy. ( see crystasl pics )
• Notable Occurrences include Durango, Mexico; Bancroft, Ontario; Germany, Russia. and Madagascar.
• Best Field Indicators are crystal habit, color, hardness and look.

Reddish Orange Apatite Crystals