I'd try the safe standard techniques:
- remove the oil with a dish washer or hot water + dish-washing soap (like Dawn)treatment, then resurface with nylon (Scotch Brite) pads; then use Columbia's recipe for re-finishing their balls.
See
http://columbia300.com/eps/eps.cfmFor the Icon2, they said: Sanding Process of 600 grit cross hatch, followed by Polish with 3M Rubbing Compound.
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