In geology, dull luster means little to no luster is exhibited by a mineral. This is due to coarse granulations which scatter the light in all directions.
A luster that is dull and earthy is referred to as "dull" or "earthy luster." This type of luster lacks shine and reflects light poorly, often resembling the appearance of natural minerals or soil. It is commonly seen in materials like clay or certain types of rocks.
These are terms that reference the mineral's luster (or lustre).
Bauxite is a rock composed mainly of aluminum oxide and aluminum hydroxide minerals. The rocks also contain clay, silt, and silica. Bauxite has a dull, earthy tone luster.
Shiny
The shininess of the metal is known as its luster. Luster refers to the way light interacts with the surface of a mineral, rock, or metal, and it can vary from metallic to dull.
dull luster looks somewhat metallic, but it isn't quite as reflective.
Coal typically has a dull or matte luster, meaning it does not shine like metals or some minerals. It can appear dull, black, and brittle in texture.
Granite has a very dull luster when unpolished.
Tellurium has a shiny luster.
The words waxy, pearly, and dull describe a mineral's luster.
the type of luster which is dull
dull but pretty
Ruby (corundum) has a vitreous or glassy luster.
dull to earthy
Cadmium has a shiny luster when freshly cut, but it can develop a dull gray patina over time when exposed to air.
Marble typically has a dull to glassy luster. This means that when polished, it can have a shiny appearance, but in its natural state, it is often more matte and earthy looking.
Quartz in general has a glassy or vitreous luster.