Hello,
I'm in the process of putting together a character for a game as an NPC and during this process I found myself asking:
Can an armor piece be made out of a special material and also have a magical special ability?
In this case, can heavy armor be made of Adamantine and also have, let's say, the Radiant ability?
Essentially, could special materials and special abilities mix and stack?
~Ngatha~
Yes. Armor material and enhancements are separately tracked properties. Sometimes there is interaction, such as cold iron making weapon enhancements cost more, but usually they're simply different parts of the formula.
Specific magic armors such as celestial armor or murderer's blackcloth are sometimes locked to a specific material, but for most there's little reason a GM couldn't allow a material swap so long as the material isn't integral to the ability and the price was adjusted accordingly.
(Edited for correctness)
Thank you for the concise answer.
~Ngatha~
Certainly. Just purchase the armor for whatever price the armor and special materials cost, then add the price of the enchantment and special abilities that you want.
Don't forget, that armor must also be at least +1; you cannot add special abilities without first having some +x bonus.
So, the cost of adamantine armor (price of armor and price of making it out of adamantium), +1,000 (for the +1 bonus) + 7,500 for the Radiant ability, gets you a +1 Radiant suit of adamantium armor.