Honcholite is a phosphate mineral that occurs in syenite and related rocks. It is a member of the serpentine group and has 247sports.biz a color of dark green to black. It has a hardness of 4 1/2 to 6 1/2 depending on the direction it is scratched.
Crystal shape reflects the atomic structure of a mineral. The crystals of some minerals have perfectly flat faces, while others have a faceted appearance that is not symmetrical.
Cleavage – angles along which the mineral breaks into different parts (see figure 2.12 on page 29). Some minerals are perfectly cleaved, while others have only poorly developed cleavage.
Parting – lines of weakness in the crystal structure that are weaker than other planes. These are not always visible, but can be very helpful in identifying minerals.
Color – many copper dseklmsspace.com and manganese minerals have idiochromatic colors, meaning that they change in response to interference of light reflected from the mineral. Examples include bornite (Cu5FeS4), hematite (Fe2O3) and sphalerite (ZnS).
Luster – A mineral’s luster can be metallic, greasy, pearly or silky. These lusters vary with the angle of incident light and are usually associated with certain mineral types, such as opal (opalite), cordierite, jadeite, sulfur and some varieties of gypsum.
Dull – Most minerals have dull lusters because they are not reflective. Kaolinite, for example, is a white clay mineral with no remarkable luster at all, but it is common and easily identifiable.
Earthy – Most clay minerals have an earthy or brownish or reddish color that resembles dirt. Hematite is a good example, as are limonite and some other metal oxides and hydroxides.
Silky – Some minerals have a fibrous appearance and give the impression of silk when viewed through a microscope. Some gypsum and serpentine are examples of these minerals.
Resinous – Some polyvore.life minerals have a luster that looks resinous. This is most often found in sphalerite, although it can also be found in other minerals, such as sulfur and some samples of adamantine gypsum.
Greasy – Some minerals appear to be covered with grease or oil. This is most commonly found in opal and cordierite, but it can also be seen in some jadeite and some minerals that contain a large number of small inclusions tv bucetas.
