In DC, most of the dope I've encountered is packaged in the typical mini ziplock baggies. No special logos or anything on them. The quality is pretty poor. The stuff is usually cut to hell with quanine and if you look really closely you can see a few brown specks here and there that is the dope.
In Baltimore, where I get all of my dope from because of the high purity, it always comes in small vials, similar to perfume vials, with different colored plastic caps. The caps mean absolutely nothing. Usually the dope itself comes in the form of tan rocks that are broken just enough to fit in the vials. You can always tell if the vials are cut or not, because the dealers intentionally leave the product as small rocks. If the stuff is powdered, it's cut.
The only exception to this is the last time I purchased from there. I got $25 vials, which is unusual. For whatever reason, the times I've seen $25 vials, it contains two $20 vials worth of dope. What made this last time so unusual is that the powder and rocks were snow white, yet the quality was amazing. The dope lasted me 4 days, when usually it would have only lasted me 2 days had I bought $20's.