[Scriptoris] Help w/brown paint! :o)

[Deanna della Penna]

Like lots of others, I love Winsor & Newton Designer's Gouache.

I've noticed for a long time, whenever I seem to buy a tube of
brownish paint--- Vandyke Brown, Venetian Red, etc-- they seem to dry
out extremely quickly, so that I only get a few uses out of a regular
14 mL tube.

Am I just really clumsy about recapping my brownish-paint tubes? Did I
accidentally buy a batch of old paint and maybe I just need to try a
different vendor? Or do others have that problem with certain kinds of
colors drying out on them?

I mix a lot of my colors, of course-- but it's nice having those
shortcuts available, and very disappointing when you pick up a tube
with a looming deadline and discovering it's dead. :o)

Thanks!
-Deanna