1830 Davignon Unl (Z9-IG) comes from the 1830 Counterfeiter family. These varieties are struck on billon, brass and German silver planchets. This variety was once thought, at least by me, to be just a modified die from Davignin 2-B. However, that has been conclusively proven to be incorrect and this is an entirely different reverse die. This variety is about 2x as rare as 1830 Davignon 2-B.
 
This example is quite nice for showing a fair amount of wear. It is estimated that this example was struck on a German silver planchet. If you collect like I do, I'm after all the different and major planchet alloys for each variety.