When I signed on with Stampin' Up! as a demonstrator part of the startup kit was the case of pastels (chalks). All of the 48 core colours are represented. I have not used them often, but one of the projects in the Simply Stamping online course offered by Heather Summers uses them. It also uses the Inspired by Nature stamp set that I really love but do not use often enough.
The floral image was stamped using Versamark and then the pastels (chalks) were 'pounced' on using sponge daubers. This project also uses the masking technique - the flowers were masked and the grass image was stamped over top and then the mask was removed.
Stamp Set - Inspired by Nature
Ink - Old Olive; Versamark; SU Pastels - Old Olive, Pale Plum, Perfect Plum, Elegant eggplant, So Saffron, More Mustard, Chocolate Chip,
Card Stock - Very Vanilla, More Mustard, Elegant Eggplant
Other - Wide Oval Punch, Modern Label Punch, More Mustard Brads
Technique - Popping Pastels, Masking