And by the way, talking about alternatives to greases: someone mentioned lard, and actually, lard is rather resistant to peroxidation, so it would work for relatively long. In the hints and tricks thread I mentioned coconut oil, also highly resistant to peroxidation and lighter than lard, as a possible paliative solution in an emergency, as a chain lubricant, or even bearings grease. I repeat: in an emergency. Like, if you are in Africa and don't have access to suitable lubricants. There you definitely will have access to coconut oil, and that'll last without deterioration, for at least a month if not more (depends on the temperature).

Another alternative is shortening. I don't know if you can get your hands on it, as it's utterly unhealthy, because of the way the lipid chains are constructed (impossible for the body to metabolize it, so it is deposited in the fat tissue and very hard to remove), but if you do, know that shortening is extremely stable and will last several months without any deterioration. Microbes avoid shortening (clearly, being wiser than us humans) as they "know" they cannot metabolize it, and it's nearly impervious to peroxidation.

By the way, this stability is what made shortening so popular in the food industry: you can keep cookies and other foods prepared with shortening, on the shelves of shops for months, and nothing will happen.