Between hornblende and Quartz which one tends to weather faster? Why?
If you strike quartz with iron or steel you can get a spark just like with flint since its the metal that's burning making the spark, not the quartz or flint. Flint and quartz are chemically the same with only some minor chemical and structural variations. Another interesting thing about quartz is its ability to show triboluminescence. Check out the link below for how to demonstrate it.
Not by striking, but by deforming it. Many butane fire starters use a piezoelectric (quartz) crystals to start the fire. So do a lot of gas barbecues. You just have to bend the crystal fast enough and far enough to cause an arc between the electrodes attached to the crystal.
WHen you spark with a flint it is the striker, usually a piece of steel, that sparks, not the flint. Flint is really a form of quartz (more or less) and does not spark just be being smacked or scratched. Neither does quartz. But it is common to get sparks off of rock hammers, picks, shovels, drill bits, etc. when you bash them into quartz. Geologists working underground make use of this.
