For sale is a vintage Eicor crystal harp microphone. This mic works great. Plug it into a small guitar amp and wail away on your harmonica!

Or, you can use it like I used to. Which is as a drum room mic through a DI box. Place it on a pillow facing upward several feet from the drum kit in the live room. Then compress the life out of it, eq it, and blend it in to taste with the other room mics, overheads, and close mics etc. Brings a liveliness to your drum sounds you might be missing.