Identify 2x2 chrome/silver emblem I want to know which sets this piece is from.

It's 2x2 in size, no writing on it except for an S or 8 in the hole.
I've tried googling terms such as chrome/silver indian emblem/plaque to no avail.
It's apparently called a "Sun Disk" (named such in an old magazine) and it appeared in 5 different sets from the 1999 Adventurers: Jungle theme.

Minifig, Utensil Sun Disk Item No: x276



Also it's supposed to be gold, but I think I've seen the old chrome gold discolor like this before.