I can't find a mark but it looks to be made of sterling silver?. (see photos for condition details).
Large Spider Ring
Sterling silver spider ring - Gem
Black spider ring - Gem
Amazing BLACK WIDOW SPIDER Sterling Silver POISON Ring
Vintage, Jewelry, Vtg 925 Sterling Silver Onyx Black Widow Spider Ring Biker Rocker Goth 9
Black spider ring - Gem
Halloween Black Widow Spider in Web Cobweb Rhinestone… - Gem
Giant Spider Ring 925 Sterling Silver Large Black Widow Spider Black Onyx Gothic
Giant Spider Ring 925 Sterling Silver Large Black Widow Spider Black Onyx Gothic
Black spider ring - Gem
Black spider ring - Gem
Giant Spider Ring 925 Sterling Silver Large Black Widow Spider Black Onyx Gothic