GENERAL GEOLOGY

Detailed explanation-1: -How it Works: Context: The streak test is done by scraping an edge of the mineral across a piece of unglazed porcelain known as a “streak plate.” This can produce a small amount of powdered mineral on the surface of the plate. The color of the streak can help to identify the unknown mineral.

Detailed explanation-2: -Streak plates are used to test minerals because the residue left on the plate after rubbing a mineral on it can help identify its type. A streak plate is a small piece of porcelain that isn’t coated with any type of glaze. Often, the color of the residue left behind is different from the mineral’s color.

Detailed explanation-3: -Place the streak plate on a table and scratch the mineral across the plate. You may have to scratch really hard to see the color. The streak color is the color of the mineral in powder form. The harder the mineral, the harder you will likely have to scratch.

Detailed explanation-4: -A streak plate is included in your rock and mineral kit to test this property. Often a mineral will have a streak of a different color than the color of the mineral (for example, pyrite has a dark gray streak, Figure 7.16). Some minerals will have a white streak, which is difficult to see along the white streak plate.

Detailed explanation-5: -Streak. A streak test is accomplished by rubbing the mineral on a porcelain plate, also known as a streak plate. The color of the streak left by the mineral is sometimes different from the color of the mineral itself. A streak test comes in handy when identifying minerals such as hematite.