Can spellcasters use it?

Quote from nitrox3690 >>

Can spellcasters use it?

 Yes. Though not druids because it is metal.

How much would this be in GP? I haven’t been able to find a price.

Can you stack it with other armor (such as Plate Mail)?

Quote from LordAnuel >>

Can you stack it with other armor (such as Plate Mail)?

 I am wondering the answer as well. But looking at some other discussions, it looks like this is considered chain armor +1 and with no proficiency requirement. It would be nice if my understanding is incorrect and it stacks!

Quote from n3krosis11 >>

Quote from LordAnuel >>

Can you stack it with other armor (such as Plate Mail)?

 I am wondering the answer as well. But looking at some other discussions, it looks like this is considered chain armor +1 and with no proficiency requirement. It would be nice if my understanding is incorrect and it stacks!

 This is considered a +1 chain shirt (medium armor). Different types of armor don’t stack together. 

on this one i added a few other characteristics.

also add-the reason for "no proficiency need" is because the armor is so finely crafted in skill that it has no more encumbrance then clothing would have. It's mitheral material and that factor also adds the ability to cast arcane spells while wearing it. this makes this the ultimate armor for eldritch knights and wizards. 

Magical yes. Mitheral no.  Gain proficiency through magic, yes. Gain proficiency through craftsmanship, no. It is a +1 magical item made by elf's.

Really amazing!!

Quote from CoZ_10 >>

on this one i added a few other characteristics.

also add-the reason for "no proficiency need" is because the armor is so finely crafted in skill that it has no more encumbrance then clothing would have. It's mitheral material and that factor also adds the ability to cast arcane spells while wearing it. this makes this the ultimate armor for eldritch knights and wizards. 

 You can cast spells in plate armor if you're proficient with it

In my games, I have added another feature to this armor to make it slightly more desirable. 

"An elf or half-elf can add 3, rather than 2, to their AC if they have a Dexterity of 16 or higher"

The thought being that a 16 Dexterity is not unreasonable for an elf, and they should be able to take advantage of their dexterity while wearing their racial armor.

I guess you could take the Heavy Armor Feat with your ASI

Quote from NullRazor >>

In my games, I have added another feature to this armor to make it slightly more desirable. 

"An elf or half-elf can add 3, rather than 2, to their AC if they have a Dexterity of 16 or higher"

The thought being that a 16 Dexterity is not unreasonable for an elf, and they should be able to take advantage of their dexterity while wearing their racial armor.

That is just giving them the medium armor master feat for free. The elves already get loads of stuff (darkvision, age slower, access to elven accuracy feat, extra skill) I don't think they need a free feat on top.

Considering that they only get this armor if I give it to them, it would be in lieu of +1 armor, and they only get the "feat" benefit with this specific armor, it isn't as big a deal as you make it sound.

They will be upgrading to magical armor soon enough anyway.

I usually rule it that some can add their full Sex bonus since its Elf made. 

like most armor no

Can chain shirts be worn under regular armor?

GnashLopper, no body armour stacks in 5e 👍

It specifically says that it's usually worn between layers of cloth and leather though. I imagine mechanically it would still be the same, but that sounds like it can be worn with other armour. 

Quote from CoolKoala >>

I guess you could take the Heavy Armor Feat with your ASI

 You could not. You can wear this armor as though you are proficient with it, but you are not unless you are proficient with chain shirts already.