The very first thing you should do is re-examine your powder storing habits. You should never have another powder container on your bench that is different from the one you are currently using. In other words, one can at a time on the bench.
You will get advice to dump it on the flower bed, burn it up in the back yard, etc.
What I would do in your case: if you haven't moved the container or foolishly shaken it, you should use a flashlight and try to scoop out as much of the Unique as possible off the top. (That powder can be poured on the flowers or burned.) Then shake it up a lot to get a homogeneous mixture of any Unique that might remain. You should end up with about a pound of 99.9% plus of Red Dot. Since Red Dot is much faster than Unique, you shouldn't have any problems using it as Red Dot, but taking extra care with that pound to work up loads slowly.
I honestly think you would have to really work at it to cause any damage to anything with a slight mixture of those two handgun powders. Now, if you had mixed 4227 and, say, 4350, we would have a different tale to tell.
