Kiiltävälustre

Kiiltävälustre, also known as glossy lustre, is a type of lustre that gives a mineral or rock a shiny, glass-like appearance. This lustre is typically seen in minerals that have a high refractive index and a smooth, even surface. The term "lustre" refers to the way light interacts with the surface of a mineral, and glossy lustre is characterized by its high reflectivity and the ability to reflect light at a wide range of angles.

Glossy lustre is often associated with metallic minerals, such as pyrite and galena, which have a shiny, silver-like appearance. However, it can also be found in non-metallic minerals, such as quartz and feldspar, which have a more glassy or vitreous lustre. The intensity of the glossy lustre can vary depending on the mineral's composition and the conditions under which it was formed.

The glossy lustre of a mineral can be an important diagnostic feature in mineral identification. For example, the high reflectivity of pyrite can be used to distinguish it from other sulfide minerals, such as galena, which has a duller lustre. Similarly, the glassy lustre of quartz can be used to distinguish it from other silicate minerals, such as feldspar, which has a more pearly or earthy lustre.

In summary, kiiltävälustre is a type of lustre that gives a mineral or rock a shiny, glass-like appearance. It is characterized by its high reflectivity and the ability to reflect light at a wide range of angles. Glossy lustre is often associated with metallic minerals, but it can also be found in non-metallic minerals. The intensity of the glossy lustre can vary depending on the mineral's composition and the conditions under which it was formed.