I suspect you're actually describing "BLC 2?"
If you have the powder I think you do, it's actually the predecessor of BLC 2. That would be labeled BLC.
I don't have any of that powder left but it's a very good powder for a lot of cartridges, from 222 Rem on up to 30-06 with mid weight bullets 150 grains or less.
I'm wondering if it was from the lot that old Tom Higginson brought in close to thirty years ago?? Does the can have AmmoMart on it??
If it is the earlier BLC, it might be a bit slower than BLC 2 and the loads listed for it in manuals should be OK but as a caution start low and work up your load. It likes magnum primers to give consistent ignition, just like all ball powders seem to.
You don't mention how much of this powder he gave you. It's a real pain/expense using up most of a small lot of powder to develop a load and not be able to find any more with the same burn rate.
I took the last couple of pounds of what I had left and mixed it with a powder listed as S2924, which was also from ammomart and supposedly identical to BLC2.
If you only have a part can of it, my suggestion would be to just get rid of it, or buy another can of BLC2 and mix them together to get a usable lot.