Persian Blue is one of Carder's copper based blue glasses. Similar in color to Celeste and Rose Blue but it has a slightly greenish cast. It is almost always found incombination with Britstol Yellow reeding and a diamond optic. It is one of the copper blue's that will fluoresce under black light, inidcating that it might contain uranium.
The Bristol Yellow Reeding seems to be unstable as on most pieces the reeding is delaminating. This was typically caused by a mismatch in the thermal expansion of the glasses at the time it was applied. The Bristol Yellow also takes on more of a green cast caused by the Persian Blue reflecting though the yellow.
