Suprema

This creamy white, just slightly translucent material is a glass-ceramic like Corning Ware, but with a different composition.  The more significant difference though, is that Suprema is glazed, and this glaze acts as a compression layer which substantially increases the strength of the product.  This makes it very similar to Vitrelle’s three layered structure, where the two types of glass have differing co-efficients of thermal expansion.  Suprema’s glaze and base material have a similar co-efficient mismatch.

Examples of Suprema:  Provincial Blue mug, Restaurant Ware ramekin and Winter Holly mug.  They are marked with the 'Corning' brand name.

This is the one material that made the perfect partner for Corelle.  It's thin, strong, glossy, microwaveable, lightweight and a good colour match too.  Suprema mugs made to match Corelle can be either white or Sandstone in colour and they are marked ‘Corning’ with an approval for microwave use on the bottom. 

The advent of Suprema glass-ceramic in 1986 signalled the demise of opal Pyrex and Centura as the favoured materials for Corelle-matching cups.  A beige-tinted version of Suprema was patented late 1990, and the new Sandstone cups would have found their way to retail shelves in 1991. 

It seems that 1998 was the final year of Suprema's production, and since 1999, Livingware sets have included imported stoneware mugs.  For the more upscale product line, Impressions, it was time to transition to real Corning Ware cups in white and Soft Beige.  But this interval was short-lived, and currently all cups and mugs are made of stoneware.

Although this example is a commemorative item, the plate itself is Suprema restaurant ware.  The artwork is dated 1993.
            
Suprema also replaced Centura in the restaurant ware line which was branded as Pyroceram Tableware or Corning Pyroceram.  Some pieces like cups, ramekins and creamers are embossed on the bottom simply with 'Corning'.  As a microwave-safe glass-ceramic, Suprema was more versatile than Centura.

Related Articles:

CornerStone Cups (1983)
Images Cups (1986)
Flared Mugs (1986)
Pattern List: Occasions Cups
Pattern List: Sculptured Cups
Enhancements Cups: Compare Corning Ware & Suprema