Help: Cartridge identification with a gold “M”

I have an old cartridge, its black with a large gold �M� on the front. Any ideas on the brand/model? Also how do I tell if the needle is still good, I seem to recall that it was bent at some point, but it looks fine on visual inspection?

I think it's a Madrigal.
Madrigal Carnegie cartridge made by Benz; wonderful cartridge
microscope is best way to examine needle; buy a cheap one