Heat marks and water rings on wood

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Try this - Take equal parts of baking soda and regular white non gel toothpaste and mix into a paste. Then take a clean soft white cloth and dampen the corner with water and dip into the paste.
Buff the marks with a gentle circular motion for a few minutes. Wipe the area clean, and buff to a shine, and follow with furniture polish for a protected shine. If marks or water rings remain after about 5 minutes of buffing the marks must have penetrated the wood and you will have to refinish the piece of furniture.