Hardness refers to the strength of the forces holding atoms together in a solid mineral. The Mohs scale will tell how easily a mineral can be scratched. It has a range from 1 to 10. Diamonds are a 10 on the Mohs scale. They are the hardest minerals in the world. The color of a mineral is often easy to identify. Many minerals are found in a range of colors. This is true for diamonds also. They can be yellow, brown, blue, green, orange, purple, black, pink, red, or colorless. Colored diamonds have impurities that cause them to change colors. Colorless diamonds, however, are very pure. Luster refers to how a mineral looks when it reflects light. A minerals luster could be metallic, dull, pearly, or adamantine. Diamonds have adamantine luster–their brilliant sparkle. Streak refers to the color of the powder left by a mineral. Streak is often found after a mineral is scratched on a porcelain tile. The color of the streak left on the tile helps to identify the mineral. The streak of a diamond is white. Paragraph 5 of this passage mainly tells about