Being embossed rather than incised, and the material being glass, it is obviously molded in rather than stamped. The following are general representations of the various backstamps, which may not look exactly the same on all shapes. Promotional patterns may have been available for as little as a holiday season or a year, standard patterns from two years to as long as a decade in a few instances.
The early clear glass Pyrex ware backstamp was a simple circle with PYREX in an all-caps serif font with Corning Glassworks' CG monogram above and below. The backstamp on the earliest color ware included the word PYREX with the abbreviation T. Other Considerations The earliest colored nesting mixing bowls have a deep base ring, the bases on later ones being almost flat by comparison.
In our 2009 survey, 86 percent of the Usage Panel accepted over with the meaning "more than." This usage is fully standard.
Mortar is a workable paste used to bind building blocks such as stones, bricks, and concrete masonry units together, fill and seal the irregular gaps between them, and sometimes add decorative colors or patterns in masonry walls.
In its broadest sense mortar includes pitch, asphalt, and soft mud or clay, such as used between mud bricks. Cement mortar becomes hard when it cures, resulting in a rigid aggregate structure; however the mortar is intended to be weaker than the building blocks and the sacrificial element in the masonry, because the mortar is easier and less expensive to repair than the building blocks.
Gypsum mortar, also called plaster of Paris, was used in the construction of the Egyptian pyramids and many other ancient structures.
It is made from gypsum, which requires a lower firing temperature.
├ A Glossary of Terms ├ Dating Pyrex Kitchenware ├ Pyrex Opal Ware Shapes ├ Pyrex Ware Patterns │├ Pyrex Pattern Browser │└ Pyrex Pattern Timeline │ ├ Standard Patterns │ └ Non-Standard Patterns ├ Pyrex Model Numbers ├ About Pyrex Item Numbers ├ About Pyrex Colors ├ Pyrex Solid Colors ID Chart ├ Pyrex Promo Accessories ID ├ Vintage Pyrex Advertising ├ Pyrex Catalogs & Brochures ├ Patent Database ├ Videos & Links └ Accessories/Books/Apparel Estimating the age of Pyrex opal glass kitchenware can most often be done by observing a few basic characteristics. Production of opal ware commenced in 1936 after the merger with Mac Beth-Evans Glass Co. The plant there would be used to produce a more durable messware for the military. in a downward curve below forming a broken circle of sorts around the name. No model number or other information was included on the earliest pieces. 1950 or shortly thereafter, the registered trademark symbol "®" was added below the name, the encircling wording became TRADE MARK above the name, with MADE IN U. These appear to be related to either molds or production runs. Patterns The first pieces to have a decorative graphical pattern applied appear to have debuted in 1956.