Sulfur. (Edit: Just at a guess)
From what I can determine from my web searches, sulphur is it. Apparently there are some yellow-sulphur-sand dunes around Vancouver as well. Whew-iie! I'm sure those were some happy people after filming. Sulphur, Oklahoma is near where I grew up and there is a state park there with some great swimming holes if you can deal with the smell. The name is literal.
In one episode of Highlander, there was a swordfight and quickening at a sulfer mine. Big yellow piles of the stuff.
Hah! I just watched that episode last night, Daniel. It was on my TiVo from earlier in the week...
Back to Tru Calling -- I've decided that we must hope for follow-up on Rebecca -- that way CKR can come back and have more to do.
Maybe Tru will have to save the baby's life when Rebecca is forced to leave it in her apartment, or in the care of someone unsafe while working or during auditions so that she can keep them both from starving. Or she'll have to go much further back in time to make sure she didn't conceive in the first place.
Madrigal -- I think you've got it.
She goes back in time and SHE has the affair with the CKR character so that Rebecca never does and therefore never conceives that baby.
Oh, good. Sumi's mind went to the same place mine did.
I'd like to see more Hudson Leick. This is the woman when asked how she was able to play such an evil character as Callisto on "Xena" answered, "I grew up a slight girl named Heidi. It's easy."
Or if they feel they need to keep the baby around, Tru could alter things so that Rebecca gets pregnant by a different guy who's not already married and planning to stay that way. Then she might be able to have the husband she wanted around during procreation.
I vote that Eliza throws herself on Callum to save Hudson....
Or they could have Eliza throwing herself on Callum and then Hudson. If they're not going to put that much thought into the show, why not just have Tru go into the past and only sleep with the guest star? They might still die, but they'd die happy.