I do when my third eye chakra is closed or almost closed....when I don't use my gifts and come away from my spirituality for awhile, I find that when I meditate my third eye almost hurts. Maybe you are closed off there, and therefore it will be slightly uncomfortable....but the more meditation you do, the more open you will become.
Crystals form when they are in high pressure.
glass and liquid crystals that react to pressure
because nothing in nature is flawless, crystals either grow from minerals or form under lots of pressure and heat
crystals
It depends on the mineral and the pressure and temperature at which it forms best.
heat and pressure
Increased pressure causes temperature to rise, enhancing ice crystal melt.
Pressure developed within a volume of molten metal.
It forms a face-centered cubic crystals. Under pressure these change to hexagonal close packed (hcp) crystals.
Metamorphization-the process of heating and putting stone under great amounts of pressure. The slower the rocks cool, the larger the crystals.
9
It is a clay sample where the largest effective pressure previously experienced is larger than the current pressure