system
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human
[General Fantasy] Is diamond armor actually any good?

So, we killed a diamond elemental.  Our mage is telling us he can shape the diamond into plate armor for us and it will be better than our steel armor.  I'm worried about how much it will weigh.  Our tank is worried about it shattering.  Should we let him do it?
gpt
Armor made of extremely expensive items tends to be magical--and the more expensive the item, the more magical it is (in direct proportion) and vice versa.  

Magic armor tends to be form-fitting (e.g. it shifts to fit the wearer) which is why you can stumble across it in a treasure horde inside a dungeon and it works immediately. It tends to be lighter than it would if it were nonmagical. Thus, diamond plate--which would be insanely expensive and thus insanely magical--would be ultra light.  

Diamond is going to have a really hard time shattering.  Depending on the type of diamond, it might be poorly conductive to electricity (bonus for you) or a good semiconductor (meaning you'd be at risk to take electrical damage). Diamond does have very high thermal conductivity, so it won't protect you from heat damage.