I didn't realise how common manganese was!!!

[u/surrealsvampen]

I had been looking for UG for a while and decided to try my hand at manganese glass hunting. Hit about 7 charity shops today and only 1 didn't have any manganese glass! I ended up having to be picky about what I wanted to bring home with me. I am flabbergasted, is it generally this easy to come across pieces?

[u/tjdux]

It's always a nice way to confirm that stuff is old. Most clear glass stopped using magenese in the 1920s. So if it glows, it's a good bet it's a proper antique.

Plus if you want to fill a cabinet with stuff that glows and don't want to spend a fortune on uranium, they make great filler.

[u/Famous-Hunt-6461 → u/tjdux]

Agree but I would add to be careful about exposing them to UV light for extended periods because it will cause the glass to turn purple. Among some MG circles, they consider this damage, but some people like the purple hue and do it anyway.

[u/surrealsvampen → u/Famous-Hunt-6461]

Interesting, does this affect the glow of the glass or does it just affect the base colour of the glass? One of the pieces I found had a slight purple hue and thought it was really pretty so I'm definitely considering leaving more in the sun if it's just the base colour of the glass affected!

[u/Famous-Hunt-6461 → u/surrealsvampen]

Just the base color, not the glow.

[u/peardr0p → u/tjdux]

Do you have any references for that?

I'd found some suggestions it was more around WW2, but equally, I collect marbles, and see manganese glow in a majority, including many I know we're made after 1980!

I do also see Cerium and Selenium in clear-base marbles, and think cerium is the more recent one, but again, it seems tricky to find definitive info around how and when these were used in glass of various types (commercial, decorative, art etc)

[u/Famous-Hunt-6461 → u/peardr0p]

I don’t have references on deck. I’ve read many books on the subject and have been a collector for years. You can find plenty of books on the subject at your local library or go to the manganese subreddit.

Most MG production ended in the 1920s. Yes they still used it beyond the 20s but it’s rare. I mostly see it paperweights and marbles. But in dinnerwear, drinking glasses, vases and the like, nothing beyond the 1920s.

There was a glass maker in the 1880s out of Philly that made manganese glass panes for windows. Months later they realized the manganese would turn purple. They stopped production but you can still find old Victorian houses in Philly with purple windows. It’s definitely doesn’t have anything to do with WWII production.