I took the Broach to a local jeweler and they cleaned it and put it under a gem microscope. The one pic shows under the microscope. There is faint evidence of a C before the Z but it could also be me wanting to see it. The jeweler said like my initial estimate that it was ZEOH. However looking at the O in the ZEOH and compare it to the O in SLOVA I could be convinced they are significantly enough different to allow the first to be a C instead of O. I could convince myself it is CZECH. Btw the broken stone and lose scroll work fell out in ultrasonic cleaner.
Also thank everyone for the comments so far but still don’t have a definitive answer to when and where for this broach.