To the best of my knowledge, this is a cast counterfeit of the crude style "LVO" 8 Reales. Seems to be of a manufacture contemporary with the legitimate issues evidenced by the crosswise hand filed edges, the small areas of pitting, and the soft, rounded design features (instead of being sharp if struck from a die). This piece weighs 27.3 grams and XRF-ed as 89.5% silver and 10.3% copper. An intriguing piece which will make for excellent study.
 
This KM-190 is a die match to this listed cast counterfeit.
https://auctions.stacksbowers.com/lots/view/3-1ZMVN/mexico-war-of-independence-zacatecas-8-reales-1811-lvo
 
This example used the same obverse but different reverse as the above die marriage coin and this cast counterfeit.
https://www.coincommunity.com/forum/topic.asp?TOPIC_ID=112430 
 
A similar but different cast contemporary counterfeit variety sold for $1,116 in 2013; I have not found any other contemporary counterfeits of this coin type which have publicly sold.
https://auctions.stacksbowers.com/lots/view/3-25SF3/mexico-war-of-independence-zacatecas-contemporary-counterfeit-8-reales-1811