Russ,
I've heard that if chalk is kept under normal conditions for more than a few years, you can expect major moisture problems in the chalk, causing you to miscue with increasing regularity. I would consider getting rid of that OLD, pre-flag chalk. It's probably not worth having.
The same thing goes for that Blue Diamond chalk. If you bought a case of that, you should be trying to get someone to take if off of your hands.
(So just in case you want to trade a case or two of that old pre-flag, high-moisture content Master chalk for some NEW, FRESH, MASTER CHALK, just give me a buzz) (I guess I would trade off a case or two of my NEW, FRESH Master Chalk just to help a guy out).
Damn Joey, I know you're a nice guy... but that offer is really hard to pass up!!!
If it weren't so expensive to ship Pre Flag Masters chalk due to the high lead content, I would take you up on your generous offer in a heartbeat. But I don't want to deal with the EPA and all that.

Take care buddy!!