Which characteristic do samples of the mineral pyroxene normally exhibit?

Samples of the mineral pyroxene normally exhibit HARDNESS OF 5 TO 6.
Pyroxenes are a group of rock forming minerals, which are found in both igneous and metamorphic rocks. The mineral is composed of many elements including: sodium, iron, magnesium, calcium, manganese, zinc, lithium and other smaller ions. They are also usually found in volcanic lava.

It's cell theory. easy name i would think.

Ten percent of energy is transferred from sun to the level indicated.