Thanks for the correction…..you are right, it is manganese. The jar show is pretty overpriced but you are more likely to find the more rare jars.@Perplexed is right about the value, those are pretty common jars.
Manganese is the additive that turns the glass purple in the sun though. Most manganese came from Germany and went out of use in the US in 1915 because of WWI.
There's a bottle collector's show every June at the Tulsa Fairground in whatever they call the IPE Building now held in conjunction with the flea market. Lots of glass and advertising items.