I just got a vial of wlp005 British ale yeast from LHBS and prepared a starter last night. It had a best before date of June 27th, so was fairly fresh and looked fine. When I started preparing the vial to pitch into the starter the yeast cake refused to mix with the liquid. After lots of vigorous shaking the yeast finally broke free but was like a rock. After much more vigorous shaking, it slowly broke up some more, but refused to really mix with the fluid. It looked like a really dense snow globe. When I opened it, it smelled OK, maybe a little cidery. With nothing to loose, I went ahead and pitched the yeast and it seemed to finally break up and blend with the starter on the stir plate. When I got home today, it was looking pretty normal and appeared to be growing (the starter was lighter colored like normal anyways). Now it looks like it is slowly turning back to snow and almost seems to be separating into two layers even while mixing. I'm guessing it may be trying to floculate. Here's a pic of the vial before pitching. I've never used this particular strain before, and never seen yeast act quite like this before. I'd love to here some opinions on what you may think of it.
