Olsen M-102 Crystal Microphone 1950s RCA 77 Clone-Working!

Here's a blast from the past! This is an "Olsen-77",actually a model M-102 Crystal Microphone from the mid 1950s...Working! These mics were sold by Lafayette Radio,Allied Radio,and likely early Radio Shack...And -Olsen! It's very unusual to find any natural mineral (rochelle salt) crystal mics from the 40s/50s working.This one is not only working,it's the "Polydirectional/Multi-Pattern" Model.It has two functioning AIWA crystal elements switchable from "S" to "P" I'm guessing Series or Parallel,which would give Omni & Cardioid pickup patterns! Mic output is useable,certainly unique,and also not anything like it's famous counterpart! Finish is VG+,great chrome,no dings dents all hardware A+even original grillecloth is intact.Vintage Snyder,Phila. deskstand is also included for display.