What is Wonderstone? Is there any source indicating that it was created pre-1982? I'm trying to find a reference to wonderstone in D&D pre-1982.
Wonderstone did not appear in D&D until 1983.
It first appears in Dungeons & Dragons in the article Gems Galore by Ed Greenwood, in Dragon #72 (April 1983), which introduces numerous gemstones which, as the article mentions, are not already listed in the AD&D Dungeon Master's Guide. The AD&D DMG was famous for well-researched and unusually detailed lists based on real-world information, so if even AD&D didn't include such an obscure mineral as wonderstone, it's unlikely that earlier sourcebooks did either.
We can rule out any of the 57 or so pre-1983 TSR publications by a process of elimination. I have, where possible, also personally checked these sourcebooks to confirm.
- We know it's not in the AD&D DMG because the article tells us so. It's not in the PHB since that book didn't detail gems.
- If it's not in extra-detailed AD&D, it's certainly not in any earlier core book or treasure lore book (White Box and Supplements, Holmes/Moldvay Basic, Monster & Treasure Assortment)
- We can assume it's not in any monster, deity of NPC book (AD&D Monster Manual, Fiend Folio, Rogues Gallery, Deities & Demigods).
- Adventure modules of the Original D&D era listed gemstones by value or range of value, not particular names, and on the rare occasion where names are used, it's always a very well-known stone like diamond, not obscure detailed names for ornamental or semiprecious stones (that was introduced by AD&D), and even AD&D didn't have wonderstone in its list. This eliminates about 38 of the 57 or so books in that date range.
- This leaves only the World of Greyhawk Folio (1980), which refers only to gem categories, and refers readers to the Dungeon Master's Guide for further detail.
This only leaves Dragon magazines. Only one earlier article on gemstones appears in The DragonDex, in Dragon #8. I've checked this article and, while it mentions many gemstones, it does not include wonderstone or rhyolite.
Therefore, it is almost certain wonderstone was first added to D&D by Ed Greenwood in his April 1983 article, and did not canonically acquire its magical properties until much later.