All About Pocket Knives

Picked up a few knives today at a yard sale and among them was an Imperial 4622 Folding hunter with a Frontier stamp and shield.The handles are white(sort of)and made of some type of plastic that resists cleaning and polishing. The only way I could clean them was to scrape the top layer of scuzz with a knife blade.Using Mother's Mag Wheel polish on them only took material off the pins and bolsters(blackening the rag) and depositing it on the handles.
Anyone have a clue on what this stuff is and how to clean it? It isn't casein plastic(that stuff smells like sour milk which it is when it deteriorates)and it will take a great shine. Here are a couple pics of the knife. BTW it was $10.

Here is a link to a custom knife by John Lloyd. He has what is said to be the largest collection of vintage handle material.
This knife is handled in "Richlite" a synthetic that "wears like iron" and looks somewhat like the handles on your Imperial.
http://www.vcmcustomknives.com/richlite ... -clip.html
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