It's an "apothecary weight". The markings are apothecary-shorthand for "one ounce".
Reference for symbols usage: Wikipedia.
The "ounce" referred to is probably not the avoirdupois ounce, or the troy ounce, but the "apothecaries ounce". The "ounce" was defined differently in different parts of Europe; this map (also from Wikipedia) shows how much an apothecaries ounce weighed, in grams, in each area. If you weigh your object, you might get some indication of roughly where it came from.
Reference for symbols usage: Wikipedia.
The "ounce" referred to is probably not the avoirdupois ounce, or the troy ounce, but the "apothecaries ounce". The "ounce" was defined differently in different parts of Europe; this map (also from Wikipedia) shows how much an apothecaries ounce weighed, in grams, in each area. If you weigh your object, you might get some indication of roughly where it came from.
Don't say "infinitely" when you mean "very"; otherwise, you'll have no word left when you want to talk about something really infinite. - C. S. Lewis






















