The clutches in my vintage and veteran Fiats are multi-plate metal plates - 29 plates or so of them in each clutch assembly. They are made out of a particular grade of steel and needed to be frequently lubricated with a kerosene/oil mixture. Lubrication was done by way of a syringe type affair injecting the solution into a hole specially provided in the clutch housing for the purpose. The owners' manual (both 1910 and 1922) gives strict instructions as to how frequently this job had to be done. (every 3 months).
In recent times some here in Australia have tried to have these plates remade, using laser cutting technology to remanufacture the inner and outer rebates to fit the splines of the output shaft and the input shaft to the gearbox. This has generally met with failure, as the laser apparently generates micro-cracks all the way along the cutting edge of the path of the laser. The ones that I have are 90 years old, and I have recently 'deglazed' the surfaces (read patience and very fine engineering tape) to restore them to top condition.
When driven with the respect that the car deserves, the clutch works very smoothly, but pays you back if you try to hurry a gear change, which also has a lot to do with the 62kg flywheel on a rather spindly and whippy crankshaft.
Bill.