Glass is arguably the most esoteric category in antiques. Few examples bear identifying marks; original designs and permutations number in millions and copying/plagiarism has always been endemic in glassmaking.
So, most folks need all the help they can get when assessing the date manufacture and national origin of specific pieces.
As the glass specialist of the BBC’s Antiques Roadshow for the past 16 years, I have always considered it important to entertain and inform a general BBC1 8pm Sunday night audience. And that includes imparting simple rules-of-thumb to the possibly uninitiated.
However, I would never, as Mr Shaw puts it, “advocate pinging as the sole means of assessing drinking glasses of various values and ages”.
But (sensible) ‘pinging’ can be a valuable aid to identifying whether or not an item of glassware is British.
This is because most of the fine glass produced in Britain from c.1700 was in lead crystal. This practice continued for almost two centuries – until around 2000, coinciding with demise of industrial fine glassmaking and the ban on lead.
This was not the case elsewhere where cheaper formulae, including soda and chalk, remained the national standard for centuries. As in Italy, France (Baccarat excepted), Bohemia/Czech, the US, Spain, etc.
As a result, lightly ‘pinging’ the bowl of a wine glass with a fingernail can determine whether a glass is likely to be British. Or not. If it rings with a clear choral note, it could be British. If it doesn’t, it is most likely foreign.
Maybe I should add that hammers and other blunt, heavy instruments are not recommended for this purpose.
File these suggestions under: ‘Every Little Helps’.
As for scouring the base glassware – which, as Mr Shaw mentions, can “make a glass look older than it actually is” – file this practice under ‘Fraud’.