Of course 15% sounds better than 4%, but could it be you mix royalty-% with project-share-% ?
Let's assume they had given us 15% of the total project, at a POG of 1.250 US$ and maybe 1.000 AISC/oz.
15% of remaining profit margin 250 $/oz would be 37.50 $/oz
4% royalties from 1.250 $/oz = 50 $/oz
A 15% royalties deal would give Birimian 187 $/oz and Randgold & Co only 63 $/oz from 250 $/oz profit margin.
That sounds pretty good, but i doubt you can expect such a result in a negotiation David against Goliath....
And Randgold would get only 40% of 63$/oz.... That would not be worth the effort for Randgold.
In this JV Randgold gave Loncor Resources 35% of the project.
But Loncor is having only 35% of a project with a feas-study level in their hands. To become a producer and receive Cash Flow, they have to give Randgold a further stake or they have to dillute their marketcap to finance 35% of mining capex on their own...
Not sure if the Loncor shareholder gets more in the bottom line in comparison to a 4% royalty deal...