For interest, this Duroven Glass lidded condiment or sugar bowl which I couldn't resist. Lovely opaque buttermilk colour with a metal lid and tortoise shell plastic knop.
Marked MADE IN ENGLAND BRITISH DUROVEN GLASS 103-B-S-B on the base. No markings on the lid.
I've never come across their glass before but 'Duroven' appears to have been a trade name for Webb's Crystal Glass Co.Ltd.
There is also some connection with Duroglass Limited and B & S Glass Industries.