Zrex

Sometimes it takes quite a bit of time for remaining grease to turn rancid. Often depending on the humidity and ambient temperatures.

It can often take years for it to start smelling and you then wonder whats going on.

Take it for what its worth. Was just trying to prevent problems later on for folks. Being that the brain is full of fat and it will melt as soon as the water starts to creep above 150 degrees or so, often, even with detergent, the grease soaks in the inside of the skull first, where you may or may not see it.

One could soak the skull in a cutting agent like Acetone to help, but it won't and can't get to all the affected areas. I suspect one might have decent luck if the skull was hot.

But why worry about it all. Just rot it off. I've found that there are reasons for lots of things. Reasons museums request things are usually very pertinant to the life of the mount.

Best, Jeff