[Histonet] Alizarin red color differences

[Walters, Katherine S]

Esteemed Histonetters,

I have two powders of alizarin red from different sources that are two
very distinctly different colors.  I am not sure which would be the best
to use.  One is very dark red and the other is a deep yellow.  Are these
both useable  alizarin red powders?  There aren't any CI numbers on
either one.  Can they be used at different pHs? Please help me sort this
out.

Thanks,
Kathy