Chlorite Group
The Chlorite Group of minerals is a band of mostly monoclinic phyllosilicate that is micaceous that includes Amesite, Chamosite, Clinochlore (Kämmererite and Seraphinite) and Cookeite among others. The most species that are common the Chlorite Group are Clinochlore and Chamosite. Chlorite is named from the Greek term chloros for green, referring to its typical colour. Chlorite is not recognized by the IMA as a mineral that is individual so the term Chlorite can be used to denote any person in the group when differentiation between different users is not feasible. There were names being many past literary works to spell it out Chlorites with tiny variants of chemical composition. The currently accepted names are Clinochlore (Mg-rich Chlorite), Chamosite (Fe-rich), Nimite (Ni-rich) and Pennantite (Mn-rich). Cookeite (with lithium substituted for aluminium) can also be a known member of the Chlorite Group. Chlorites characteristically occur as hydrothermal alteration products of other minerals such as Amphiboles, Pyroxenes and Biotites.
Chlorites are often recognized by gem collectors as green inclusions in Quartz and are especially interesting when they form as being a coating on a crystal early in its development. As the crystal later grows larger, ie. away and around the Chlorite coating, the effect produces a crystal that is phantom. The inner “crystal” is frequently indistinct or ghostly and so the true name phant
| Category: | Phyllosilicates |
| Chemical Formula: | The general formula may be stated as: A5-6T4Z18, where A = Al, Fe2+, Fe3+, Li, Mg, Mn, or Ni, while T = Al, Fe3+, Si, or a combination of them, and Z = O and/or OH |
| Crystallography: | Monoclinic – Prismatic |
| Color: | Various shades of green; rarely yellow, red, or white. |
| Mohs scale hardness: | 2–2.5 |
| Luster: | Vitreous, pearly, dull |
| Specific gravity: | 2.6–3.3 |
| Refractive index: | 1.57–1.67 |
| Cleavage: | Perfect 001 |
| Fracture: | Lamellar |
