Marble identification reference guides are available at Collectors Weekly, Oh Marbles, MarbleCollecting.com and BuyMarbles.com to help collectors identify rare and collectible marbles. These reference guides include sample photos and detailed descriptions of the history, identifying characteristics, materials, and current values of antique, vintage and modern marbles.
To determine a marble's authenticity and rarity, MarbleCollecting.com encourages collectors to submit photos and ask questions at online marble collecting forums. They also suggest contacting online marble clubs, dealers and online auctions to learn more about current values and trends for collecting rare marbles.
Handmade antique glass marbles from 19th Century Germany, also known as "Sulphides," are some of the rarest and most highly collectible marbles, reports Collectors Weekly. Sulphides are clear glass marbles with small figurines of people or animals suspended in the center. The marbles with human figurines tend to be the most valuable.
Beginning in the 1990s, some glass artists and manufacturers began creating reproductions of Sulphides and other highly collectible marbles, according to BuyMarbles.com. The site now offers several articles describing how modern reproductions are made, which marbles are being reproduced and tips to help inexperienced collectors identify fake marbles.
MarbleCollecting.com advises collectors to attend live marble events, ask questions and see examples of rare marbles in person. The MarbleCollecting.com site includes an updated calendar listing upcoming marble shows and conferences.