I think I found the information I...

I think I found the information I remembered.

http://www.troyres.com.au/images/files/technical/NI_43-101_Technical_Report_West_Omai_Guyana.pdf

p. 14

"Offset of the cost of certain infrastructural works of general benefit to Guyana against themineral royalty."  Means Troy is allowed to deduct from royalties anything they spend on infrstructure for general use. US$100 spent on road building for general use = US$100 less in royalties.

"Deductibility of royalty payments against corporate taxes." I would think this mean if Troy pays US$100 in royalties and owes US$150 in tax liabilities on earnings of US$500  they are allowed to deduct the $100 against the $150, so only $50 in tax to pay (initial earnings US$600 - US$100 royalty - US$50 = US$450 net earnings = 75%).

It could also mean the royalty is earnings deductible just lowering taxes (US$600 initial earnings - US$100 royalty - US$150 tax on earnings of US$500 = US$350 = 58.3%). But in this case it would be unfortunate wording and why state something which is just the standard procedure?

At least we are safe from any tax and royalty changes for 15 years.