Decorative patterns are also key to determining the glassware's value. Lucky in Love, a sweet pink and green design, is prized for its rarity and promotional production. Wright notes that Amish Butterprint, Pink Gooseberry, Snowflake Blue, Crazy Daisy and Friendship are also considered valuable in the Pyrex community.
Pattern. Patterned Pyrex—such as the 1956 Pink Daisy or the 1983 Colonial Mist—tend to be valuable as a collector's item. Other popular patterns include the 1957 Butterprint, which features an Amish couple and their crops, and has been valued at a few hundred dollars.
If it's all caps “PYREX,” it's vintage, made of borosilicate. If it's lower case “pyrex,” it's new, and it's soda lime. (In Europe, Pyrex is still made of borosilicate. So these recommendations only apply to Pyrex in the United States.)
Pyrex dishes also hide a little secret code: Many contain a three- or four-digit number that corresponds to a specific dish. A series of Mixing Bowls will feature 401 (1.5 pint), 402 (1.5 quart), 403 (2.5 quart), 404 (4 quart). The iconic two-quart green-and-white casserole dish is a 232.
Each Pyrex piece is assigned a model number, though some of the earliest sets of color ware pieces do not have them. Model numbers are typically found on the bottom of your glassware, though sometimes they are located elsewhere—look for them above the trademark on your dishes, and around handles and edges of lids.
In 1915, the company launched its first Pyrex line (Pyrex combined "pie" and "Nonex") with 12 pieces, including pie plates and a loaf pan. The 8-ounce liquid measuring cup came out 10 years later; early versions had a closed, D-shaped handle and tick marks made out of molded glass.
On the bottom of most every genuine Pyrex opalware article is an embossed set of markings which contains a variety of information. While technically a trademark, it is most often seen referred to as a backstamp.
The naming of these new pieces as "Cinderella" likely had much to do with the popularity of the Cinderella story current at the time both in film and on Broadway. Corning marketers also hoped the underlying theme of a coveted glass object would have a subliminal effect on consumers.
In most cases, one- or two-digit numbers are actually mold numbers that indicate the specific bottle mold or section in an automatic bottle machine. If numerous molds were identical, each one received its own number. Base numbers also indicate bottle styles or shapes, manufacturing dates, or factory location codes.
People like what they like. For others, it's all about nostalgia. Pyrex released 170 different patterns from 1956 to 1983, each with a whimsical name like Golden Honeysuckle, Lucky in Love, Pineapple Party, Cloverberry, and Angelfish.
For the home, the first set of colored Pyrex opalware was introduced in 1945 in the form of the primary color mixing bowl set.
As long as you follow the same guidelines above, vintage Pyrex is A-OK to go in the oven and can be used in oven temperatures up to 425ºF (and skip the broiler). There is one caveat to using your vintage Pyrex, though: Do not use any vintage dishes that are chipped or cracked—in the oven or otherwise.
Opaque tempered soda–lime glass was used to create decorated opal ware bowls and bakeware, and aluminosilicate glass was used for Pyrex Flameware stovetop cookware. The latter product had a bluish tint caused by the addition of alumino-sulfate.
If your glassware has a signature or maker's mark, this could indicate a rare or unique item. Check the bottom of the piece for any markings or symbols that may constitute a signature. Many glassware manufacturers, such as Tiffany & Co. and Waterford, are known for producing high-quality and valuable pieces.
It's lasted for decades. If it's all caps Pyrex, it's vintage, made of borosilicate. If it's lowercase Pyrex, it's new. And it's soda lime.
om upper to lower case signified a re-branding of the trademark Pyrex® in the late 1970s but is not a conclusive way to determine, historically, what type of glass formulation the product is made from.
In many but not all cases, the trailing digit of the model number corresponds to the capacity in pints of the bowl or dish, e.g. #043 = 1½ quarts = 3 pints. Sets were typically assigned catalog numbers similar to the model number sequence of the pieces they contained, e.g. a #470 set contained 1 each 471, 472, and 473.
As stated above, most markings will be located on the bottom. Identifiers, such as embossed markings, can be found on the side. When trying to date your glassware you can look on the bottom for Pontil marks or Mold lines as those will help you determine whether the glass was hand-blown or manufactured.
Take some time and look closely at the piece's shape, surface, weight, and quality—all potential clues for you. “Is the glass transparent or opalescent or iridescent?,” Robinson asks. “Is there any decoration that might give away what it is or who may have made it?” Look to see if the glass has been signed or marked.
Decorative patterns are also key to determining the glassware's value. Lucky in Love, a sweet pink and green design, is prized for its rarity and promotional production. Wright notes that Amish Butterprint, Pink Gooseberry, Snowflake Blue, Crazy Daisy and Friendship are also considered valuable in the Pyrex community.
Vintage Pyrex Stamp and Logo
It will have a stamp that can help you date it: 1940s and 1950s - The oldest Pyrex markings should be on the bottom of glass pieces and feature Pyrex in all capital letters inside a circle with CG for Corning Glassworks. A small figure blowing glass is included in some early stamps.
JAJ (short for James A Jobling) were the producers of PYREX tableware, casserole dishes and other bakeware in the United Kingdom from 1922 until the plant (in Sunderland, England) closed in 2007.
If the logo is in upper case lettering, PYREX, it's most likely made of borosilicate, and thus safer. The lowercase lettering is most likely made of soda-lime glass, so take extra care after any high-heat cooking.
More than 750 million pieces of CorningWare have been manufactured. In 1998 however, due to slumping sales and retooling of manufacturing plants, Corning sold off the CorningWare and Pyrex lines to World Kitchen, LLC.
Our borosilicate glass products can be put into freezer and can resist till -40°c.