Hardness is fundamental to mineral identification. Select the a mineral with a hardness 7 on the Mohs scale a. Topaz
b. Talc c. Quartz d. Orthoclase Subduction zone have a high generation of melt creating what is known as the circle of fire. How subduction zones produce melt? a. It has no real effect and it is all a coincidence b. It cools down the mantle forcing the geotherm into the liquidus field of stability c. The subducting plate melts and rise to the surface as vulcanism d. It adds volatiles to the mantle