Silver or Gold plated ~ either .925 sterling silver "plating" (a fine coating applied over other metals usually over stainless steel), or 14K to  24K gold "plating" (a fine coating applied over other metals, usually silver).

Gold Fill or Vermeil ~ a fine (but much thicker than plating)coating of 14K Gold or higher that has been layered over other metals; vermeil is 14K Gold  or above over sterling silver.

.925 Silver or "Pure" Silver or Sterling ~ pure Silver is "fine" silver, guaranteed to be 99.9% precious metal silver, and hence does not tarnish, while .925 Silver is 92.5% fine silver with the balance being the alloy, hence subject to tarnishing.    

Gemstone, Stone ~ a gemstone is a mineral compound with qualities that most people consider to be beautiful, usually a stone that when polished and/or faceted possesses a shine that glitters due to refraction in the sun or other bright light;  a stone on the other hand, is usually a non-transparent rock with either mulitple colors or layers that when polished and/or faceted possesses a shine that is a sheen or a glow but the most prized quality of the stone is the variations within the rock, as with Agate or Sardonyx.

Beading Wire or Cable - a continuous length of very thin metal, usually woven in multiple strands for durability and strength,  designed to be used to string beads of various mediums to make necklaces or bracelets;  Working Girl Gems uses only 24K Gold-plated or .925 Sterling Silver-plated metals over 49 strand stainless steel cable.