I want to purchase pastel chalks for weathering wood. Brett recommends the following colors: Raw Umber, Gold Ochre, Yellow Ochre, Flesh Ochre, Light Ochre, Indian Red, Scarlet Lake, Burnt Sienna, Winsor Red Deep, and Burnt Umber. The Dick Blick website has several shades of each of these colors. I do not know which shade to buy. Can anyone recommend a pastel number for each of the above colors. Thanks much.