[Philip]

Is it of European or African manufacture?
The shape of the lockplate is somewhat odd considering the mechanical type. In my post I identified it as a half Portuguese, half French hybrid. Original versions of this system, made in Portugal, tend to have the banana-shaped lockplates characteristic of French, or "true" flintlocks. You'll recognize the plate shape as something seen on, say, a Brown Bess lockplate, just to give an example.

The plate on your lock does not have this smooth banana profile, it has the protruding bulges typical of the earlier "fecho de molinhas". Not only that, the original molinhas locks have the rearmost bulge extended into a tapering, rounded tail. The shape of this posterior profile is necessitated by the design of the molinhas sear system which I have said is derived from wheellock sears. Your lock, which is the hybrid, has a stubbier tail; the French sear and spring don't take up as much room and a much shorter plate is needed. The nod to an earlier style of lockplate is more aesthetic than functional. The whole thing gives the impression of an artisan or manufacturer trying to get the best of both worlds -- the simpler French interior mechanism with the more traditional-looking or archaistic molinhas lockplate shape.

Based on this, I don't think that the lock is Portuguese, of the period when the system was in vogue in its homeland. If it's a Liege knockoff for the colonial trade, I would think that the major parts would be largely shaped by machine. Is the lockplate of uniform thickness throughout? Are the surfaces more or less even (albeit with file or machining marks) or is there evidence of hand forging (perhaps with some mill scale visible) that one would expect out of a native smithy? Do the screw threads look like they were cut by taps and dies, or are they hand-filed? Any stampings or markings? Answering these questions is a start in trying to figure out its origin.