[RedDevil]

I'm puzzled with the perfectly round claim.
How can a small diamond be even an approximation of a sphere?
It is the strongest crystal structure possible.
It is stronger in some directions than in others; it is bound to have crystalline edges.
To craft those into small near-perfect spheres would be very hard to do.

There is however one structure on a nanoscale that resembles a sphere very well: Fullerene, the 60 carbon atomed buckyball molecule.
Although the Wikipedia article only refers to lubrication as a side note, it is not hard to see how that round and flexible nanostructure could help in reducing friction.
If by chance the microwave process you use to produce the 'nanodiamonds' does really create buckyballs then I can believe it does actually work as a lubricant.

One simple test should reveal whether that is the case or not.
Fullerene in oil has a purple haze.
So, Mr. Arnold, what colour does your oil have?