Old white water stain on an antique table

Leave baking soda on the stain overnight. Hope it works.

Use white (not gel) toothpaste and a damp cloth. A dab of toothpaste on the cloth and gently rub in a circular motion.

Johnson suggests setting a hair dryer on warm or low and moving it back and forth directly over the mark. In most cases, the action should draw out the moisture, dry the surface and cause the ring to evaporate.

Be aware that the fix will also heat up the wax finish on the wood and melt it slightly. Try buffing with a soft rag once the water mark evaporates.

This link goes into the iron process a little deeper and more particular.

http://www.instructables.com/id/Repair-water-stains-or-heat-burns-on-wood-finishes/

This link has about 3 more remedies.

https://www.hunker.com/13423433/how-to-remove-white-spots-from-wood-furniture

Try A little Mayonnaise. Put a dab on scratch and let it sit for 5-10min. Litely Rub in Circles. Then Wipe it off.. I hope it works.. Good luck...👋🤗

Mayonnaise and toothpaste are both popular choices among Hometalkers! Let us know how it goes!