Hi Karen, I wanted to answer to you in this post so that it would be useful to others too. Two of the notations in the chart are from Schminke’s watercolors brochure.

The empty square stands for completely transparent,

        square with a diagonal – semi transparent

        half filled square – semi opaque

        completely filled square – opaque

The empty triangle is for non staining

         half filled triangle is for semi staining

         completely filled triangle is for staining

The empty circle is for non sedimentary

         circle with dots is for sedimentary

         I’m quite happy with my schminke colors but I wanted more hues so I opted for other brands. My first criteria was lightfastness, the next important property was transparency.