Sorting through my box of these, I wondered:

Is the current consensus that these are mostly pre-World War I beads, dating to the second half of the 19th century, or from the 1830s at the earliest?

Or did their manufacture continue into the 1920s-30s?

When did machine molding/faceting/firepolishing take over from the impoverished small home grinding wheels that produced faceted cane beads?