Streak color is determined from a powder rather than fragments. Streak plates usually have a Mohs hardness of between 6.5 and 7. Many minerals are harder than the streak plate.
In respect to this, what is a streak plate?
streak plate. An unglazed piece of porcelain, such as a tile, used to test the characteristic streak of minerals by rubbing the mineral across the tile.
Beside above, what is the hardness of a penny? The Mohs scale of mineral hardness consists of ten different minerals, but some other common objects can also be used: these include the fingernail (hardness 2.5), a steel knife or window glass (5.5), a steel file (6.5), and a penny. The penny has always been assigned a hardness of around 3.
Herein, does quartz leave a streak?
Streak plates have a Mohs hardness of around 7, but be sure to check your streak plate against a piece of quartz (hardness 7) because some are softer and some harder. Mineral streaks can usually be wiped off easily with a fingertip. Streak plates come in white and black.
How do you determine a minerals streak?
Streak is the color of a mineral when it is crushed to a powder. The easiest way to determine a mineral’s streak is to rub the edge of a specimen against an unglazed porcelain tile. Minerals with a hardness less than 7 will leave a streak. For many the streak will be white, so always look carefully.