Welcome to Gaia! ::

It will depend on the crystals. Those of same type (moonstones peices) or share similar mineral components are ok (ie Rose quartz & amethyst). Sometimes those of similar colours will tolerate each other (Topaz & amber, sometimes carnelian although carnelian is better with certain agates)

Although, some might surprise you. I have a piece of sodilite (blue & white speckled mineral) that likes my jade and peridot (both are green).

Some cautions though with Clear and Tourmaline quartz these ones can soak together, but mix them with other stones and they might take on the vibrational characteristics of the stones they soak with.

I find the best way to find out is to hold them in your hand. If they feel comfortable then they can soak together. If you feel a little creeped out, tingling or burning don't soak them together.

I'm not sure if it is possible for our bodies to absorb the minerals from worn crystals through the skin or not. But considering our skin can and does absorb vitamins and chemicals from the air I wouldn't be surprising if you have taken on some of the iron that gives amethysts their purple colour.

Stones do take on natural temperatures around them so it will vary depending on how close the stone is to you at the time. But the amount of use can also fluctuate the temp. Like if you have had a relatively quiet day and little need for the protective influences of the stone it might be neutral. if the need for it rises it might warm up, but if it has maxed out its potential for the day it might grow cold. It will vary from stone to stone and how well you fit to its energy

Yep they can carry a charge, or let people know when they don't want to be held.

my nephew found that out the hard way when he got his hands on some of my marble shaped stones and started rolling them along the top of a heating outlet. He yipped and dropped one of them saying it bit him.

Nope, he just doesn't play with that one stone anymore lol