The Color of Minerals

One of the things that are usually more noticeable when a mineral is found is the color of the mineral. Nonetheless, due to the fact that a lot of different minerals have the same color, color the harness test is in most occasions done first. After this, the elimination of possibilities of color can be started. It is important to learn about what things might change the color before you decide to change your reference table. The different things that can cause color variations are natural and artificial lighting; wetness, fresh surfaces as well as cold surfaces can also cause little differentiations in the color.

Mineral streaks
It was discovered a long time ago by mineralogists that when a mineral was pulverized to a powder the color it had often times changed noticeably. For example, black hematite will turn into a reddish brown color when it is pulverized. In order to standardize this type of identification, minerals are drawn across a pieced of unglazed tile that is known as a streak plate. What takes place in this test is best described as drawing a charcoal pencil across a piece of rough drawing paper and it changes a lot of the charcoal into a line of black powder. However in this case a piece of mineral is used to draw across the unglazed tile and the powder line that comes about is what is known as the streak. The color of the streak is then checked against the tables for several minerals and more elimination of possibilities is made. If a streak does not occur during the test the material is most likely harder than the seven because this is usually the hardness of the streak plate. In actuality almost any piece of tile can be used for this specific test, it is suggested to get a standard tile from a rock shop or a prospecting shop due to the fact that they are the right color. Due to the fact that the powder is usually seen on the streak plate, any color in the back of the tile can contribute to the ending result of the color of the streak.