[Paladin2]

"Today, thorium is relatively expensive - about $5,000 per kilogram."

8 gm --> $40.

Maybe not so expensive?

[babygene]

TIG electrodes are 2% thorium, and there about $6 ea... Many car headlights have 1% thorium in the filaments. As far as I know it’s not ever recycled...

Doesn’t sound expensive to me.