Silicone is especially dangerous because of its tendency to spread within the piano, sometimes causing extensive internal damage. Avoid aerosol products altogether since the over-spray can contaminate piano strings, tuning pins and action parts. An appropriate polish can help to restore luster to a dulled finish or reduce the tendency of some finishes to show fingerprints. However, it should be applied sparingly and infrequently, and all excess should be wiped clean with a soft dry cloth so no visible film remains. To prevent scratching, always dust before polishing.
Specific recommendations follow.
Go to top 5. Removing a heavy polish build-up. If your piano's finish appears gummy, oily, or streaked, it may be contaminated with too much or the wrong type of polish. Adding more polish will not correct this problem. Instead the finish should be thoroughly cleaned, then evaluated for any further treatment.