For example, beachcombers usually find a lot of white, brown, and Kelly green sea glass because these colors of glass have been mass produced since the last century by bottling companies that sell a lot of soda and beer.Colors of sea glass that fall into the rare and extremely rare categories like red, orange, yellow, pink, and turquoise come from sources such as household glassware, Depression glassware, art glass, car lights, ink bottles, fruit jars, lamps, perfume bottles, and flasks."The old glass has a watery look and refracts light differently," says Kittle of knobs gently worn by time and use.The main thing that affects sea glass rarity is whether or not its color has been mass produced over the past several decades.Such fine knobs were used in mansions at the entrances to formal areas, such as parlors and dining rooms, where homeowners entertained guests.Today, hardware-store-variety glass knobs cost as little as $10 a pair, but the materials and craftsmanship are far inferior to the vintage counterparts."It works for awhile but it always comes loose again." Prices for vintage glass knobs vary widely, depending on condition, rarity, style, and color.
The use of glass knobs continued through the '40s, but by the '50s tastes in both architecture and hardware had changed, and Americans began favoring cleaner modern lines in metals.And be wary of knobs that turn inside their metal shanks, which can't be fixed."If you get a spinner, it's worthless as a functional knob," says Kittel, who has tried in vain to reset the knobs with glass epoxy.Be sure to fit the spindle to the knob before you buy because threads and setscrew sizes can vary widely.