Salt Buck 

slang for 10 dollars

or

10 dollars worth of weed.

Guy: Do you have change for a salt buck?
Woman: Yes, I do

Salt Buck by Yogers April 5, 2008

saltbuck 

a $10 bill. From the amount of calories in a packet of salt; ten.

"Hey Joe, you got two fives for a saltbuck."

saltbuck by Vandemo April 10, 2007