There are a lot of variables when using high-metal content glasses such as lusters. Throw a reduction phase into the mix, and how long and how reducing and how hot the flame is all affect the glass. Also, glass in some cases remained transparent underneath the luster coating, and in others turned opaque (glasses that shift from one to the other often reduce to opacity.)
And if that weren't bad enough, then there are all the difficulties photographing such beads, which in effect have a partially mirrored surface, making it difficult to show both the reflective and transparent aspects of the beads (especially at the same time;) —The mirroring is why the camera shows up so distressingly well in the pix, btw.
file, photographs, made 27may08.
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