Scientific methods

[Gavin Nugent]

I am appealing to those of a technical background or insight here.

I am interested to know what, if any, scientific method/s might be available to see and photograph rubbed gold residue on blades to obtain a full image of worn cartouches?

I ask as I have what I believe to be a very important blade that with the visible gold can only offer a partial translation of two cartouches and nothing of the third.

Any direction to methods, persons or institutions that can offer help would be greatly appreciated and I am sure others here who have similar questions and could surely benefit.

thanks

Gav