Consumer Information

What color is it?: Primarily reddish brown as shown above. But it can also occur in yellow, blue, violet and grey among other colors.

What is the story behind this gemstone?: A rare and unusual gemstone more for collectors than consumers. These stones will be small and expensive. It is named for the axe shape of the original crystal formations.

Can I wear it everyday?: You can but probably will not want to.

Is it expensive?: It can be in large sizes.

Is it a birthstone?: No

What do I need to know before going shopping?: Plan on adding to your gem and mineral collection more than your jewelry ensemble. This will be a difficult stone to find. Although no collection will be really complete without one.

General Information

Source: Mexico, France, and US

Chemical: Ca2(Fe+2,Mn+2)Al2BSi4O15(OH) a long complicated chemical equation for such a small stone

Formation: Forms in metaphoric rocks whose origins are calcium rich sedimentary rocks such as limestone

Crystal System: Triclinic

Unusual Properties: None

Gemological Information

RI: 1.675 - 1.685

Birefringence: .010

Optic Character: B -

Specific Gravity: 3.27 + -

Hardness: 7

Transparency: TP - TL

Special Identifying Properties and Tests: None

Synthetics: None

Imitations: Many possible but not likely. Confused with smoky quartz

 Gemological information on this page has been provided by the