Continuity mistake: DMX uses his Porsche to slide a dumpster into the vehicle following him, staying in contact right up to the impact, so by rights the back of his car ought to be wrecked, but in all the scenes afterwards when we see his Porsche, it doesn't have a scratch on it.
Plot hole: When the "black diamond" is being turned into its dangerous form, the arms dealers get very excited. Yet all they actually see is a very pretty laser show. There is nothing to show that the object really has any destructive power. Arms dealers make their fortunes by being cautious and smart. They shouldn't be so quick to accept the claims of the bad guy and bid money on possibly useless stones.