Sorry, I don't have a photo, but I need an id on a pelargonium I recently, uh, picked a cutting of in a shopping center parking lot. (lol)

It has relatively small leaves, nickel size. The foliage is a gray green color, and heavily ruffled. The flower stalk is very tall, easily reaching 10-12" over the foliage mound. The flowers are smallish; roughly nickel size as well. But they are black! I simply had to have it. The flowers are single form.

Any ideas? It's not like I can go ask a merchant in the shopping center; like they'd know anyway!

Thanks!