Annatto Seed

I love cooking Mexican food, and was really intrigued by several recipes I came across that touted the earthy flavor profile of annatto seed. I was happy when I spotted it on Spicewalla, and quickly ordered it to add to my prized collection of Spicewalla tins of joy.
Then I attempted to use it. The seeds are harder than gravel. My mini processor/grinder made no progress, but the whisper of dust caused by its efforts left a stubborn red stain on the bowl. Mortar and pestle were equally ineffective. I did what any reasonable cook in a crisis would do, and summoned the nearest first-responder, who happened to be the brawny EMT/firefighter who lives across the street. (Also, he had a vested interest here, since I wanted the spice for the picadillo I was making for him and his wife, who are new parents) I dispatched him with a tablespoon of the seeds, and in the meantime hatched Plans B (getting him to run over a baggie of seeds with the firetruck) and C (rock quarry) He managed to pulverize the seeds but said it was the toughest job he'd ever encountered with the mortar and pestle (his spice grinder hadn't worked, either) All that, and I couldn't taste a difference in the picadillo.