How very interesting Steve to see the Boysenberry and Raspberry there together on cotton. I use raspberry a lot(prochems) on silk and looking at your pics, it compares better to the boysenberry than than raspberry. Interesting color shifts between the 2 types of fabrics.
Any
pure unmixed MX dye will be the same color on silk and on cotton, if both fabrics start out the same white, but the pre-mixed colors, having been prepared for cotton, are quite unpredictable on silk. It might be handy to make a list of what colors specific cotton-standardized mixtures produce on silk. So, as a start, we now know that you have found that ProChem's raspberry on silk looks much like ProChem's Boysenberry on cotton, and I seem to recall that ProChem's cotton black makes an olive green on silk.
Can you tell us about any other observations you've made, of what colors you get on silk using mixed colors that were standardized for cotton?
Paula