@Cobguy, originally chimo is made with urao - an alkaline mineral, containing sodium sesquicarbonate (a compound of sodium carbonate, sodium bicarbonate and water, Na2CO3.NaHCO3.2H2O), mixed with tobacco at 1:2, 1:4 or other ratios in the second stage of preparation. Some manufacturers use only sodium bicarbonate, others - lye made from ashes; chimo with lye is considered the strongest.
Here’s the link to a very interesting Dorothy Kamen-Kaye’s report on chimo -
CHIMO: AN UNUSUAL FORM OF TOBACCO IN VENEZUELA (1971):
https://www.jstor.org/stable/pdf/41762271.pdf?seq=1
You need to sign up there to get a free access to the article, it takes just a few secs. It’s a long read, but really worth your time.