It has no visible mineral pieces in it and can have sharp edges. It used to be used for making cutting tools a long time ago. It is made by very quick cooling and hence solidifies into a glass. It has different colours from the different minerals the translucent is quartz and the pink is potassium feldspar. There are also flecks of mica.
Granite is hard and dense.
Granite is pushed up from below the earth's crust and is a common igneous rock. It is also dense, mostly made of feldspar. Basalt is the main form of lava that has solidified. The Giant's Causeway in Northern Ireland is basalt.