Originally Posted by mmaher94087

A drop of penetrating oil like Liquid Wrench may help. The BIG unknown is whether or not the grip screw is rusted to the escutcheon in the ivory. The key to success is patience, patience and more patience. Let the oil soak for a while (like three days) before trying to remove the screw. It is very important to not get any oil between the escutcheon and the ivory as that sliver of ivory is the only thing that keeps the escutcheon from spinning (and not coming loose from the screw). Wipe off any residual oil before trying to remove the grip screw just incase it wants to drip or run on the ivory. When you try to loosen the screw; watch the escutcheon and if it moves, STOP! We'll have to go to plan B.

Two things come to mind: In your photo of the broken grip and frame; it looks as if the locating pin (center of the bottom of the frame) has been removed at some point in the past. There is a hole there but I don't see a pin. Most often this pin will chip/break the bottom of the grip from improper removal such as prying from the top of the grip.

Secondly, from my experience with ivory (Elephant, Walrus and Mastodon); your grips look as if they checked from age (they dry out) and, through use, collect debris like skin oil in the checking. The debris works like a wedge and, at some point, causes the ivory to fracture along the grain like a piece of wood. A small bump might be all it needs to splinter. Your photo of the fractured edge shows the browning of the checked area that led to the fracture and the clean yellow-white of the fractured surface. I believe these ivory grips can be repaired (depending on the condition of the missing piece).

Lastly; NICE WORK!