A 2012 entry on the Staffordshire Hoard blog takes an "up close and personal" look at the use of glass in the gold artifacts of the Hoard. While the majority of gemstones in the objects have been identified as garnets, a number of the colored, transparent inlays are glass. The article includes a number of photos.
From the article:
Most of the glass used in the Staffordshire Hoard has survived burial in good condition but some show signs of weathering and deterioration. The Hoard contains examples of transparent coloured glass (red and green), as well as various colours of opaque glass. The original appearance may not always be obvious due to deterioration and scratching of the surface. To date, 17 objects have been found to contain glass inlays.