Heat embossing on vellum is one of my favorite techniques, I'm doing it all the time

I like Versamark ink with Ranger Seafoam white embossing powder, just love the look of it.
Try to keep the heating time as short as possible. Move on to the next spot as soon as the embossing powder melts.
If you're interested, here's a link to all vellum posts on my blog, I usually list the inks and embossing powders:
http://stampingmathilda.blogspot.com...h/label/vellum