Turgite over Quartz - Spain #6 Rare Crystals_Aquamarine The colour is caused by

The colour is caused by the reflection of the microscopic inclusions within the obsidian

It's advised to keep away from humid environments if possible as it is soluble in water

This Malachite specimen has a velvet

this material has been renamed by dealers to 'Chocolate Labradorite'

sometimes grey/brown

Turgite over Quartz - Spain #6 Rare Crystals_Aquamarine The colour is caused byThis iridescent Turgite coating over Quartz specimen is from the San Valentin Mine in Spain. You will receive the exact Turgite specimen shown in the pictures. Turgite is a trade name used nowadays to refer to Iridescent varieties of iron oxide minerals, most commonly Goethite or Hematite, that often coat other minerals such as Quartz. As it isn't a single, defined thing, it isn't classified as a mineral, and it's usage had changed over the years,