Amal posted the instructions above this post that @NiamhAstra posted on the discord 
It’s coated in “amorphous silica,” not crystalline afaik.
From our observations, it does not irritate the skin but there isn’t a whole lot of data or even studies about it.
I would not voluntarily breathe it in
But my Skin healed off normally and didn’t look irritated at all.
That depends on the amount of UV radiation and some other factors.
What I found in several resources is that it will start to get slightly dimmer after like 5 to 20 years.
@Spyfoxls had one for over 10 years and it has not really gotten any dimmer yet.
The skin does a good job with UV protection, so it should last really long.