For non-professional testing of glass, beyond obvious visual clues, we are probably limited to UV Reaction and Specifc Gravity Measures. Both of these have been discussed to various degrees in this Board and a search for "uv testing" and "specific gravity" (or "sg" or "density") will show several messages. In one particular message
, I gave some basic thoughts on UV Testing.
To make truly meaningful tests of Chinese versus Murano weights, using either method would require access to a lot
of examples from both countries and from the various makers in those countries and from the various periods of manufacture. And the Chinese category should include items from Taiwan as well as the mainland.
However, the equpment required would be much easier to obtain than the weights and the knowledge of confirmed attributions.
For UV testing, I suggest a dual-wavelength light with longwave (blacklight) and shortwave bulbs. There are often differing UV reactions under the different wavelenghts and this can help to draw conclusions. Reliable lamps can be obtained through the UVP company
, which has a wordwide distribution network. But note that such lamps are not the "cheap and cheerful" ones readily availble through eBay.
For Specific Gravity Measures an accurate set of scales is needed. I use a beam-balance, but my results have not been wholly successful (no doubt due to my own lack of precision rather than any fault with equipment). An alternative system has been described and illustrated by Alan in this message