White marks on wood are usually moisture in the finish. Dark marks are stains in the wood. Sorting which you have decides whether heat, polish, or sanding is the right next step.
Quick identification
Cloudy white rings and haze sit in the film. Black or gray blotches that remain after the surface feels dry are typically in the wood fiber.
Clear white haze
Try a dry cloth and low iron (no steam) in short passes. Mild toothpaste or baking soda paste can help light haze—test first, wipe clean, then polish. Recoat if the film is rough.
Dark stains
Sand to clean wood. For iron/tannin stains, oxalic acid wood bleach can lighten after sanding; rinse, neutralize, dry fully, then restain and finish. Follow product safety labels.
Match the finish
Whatever path you take, rebuild sheen to match the surrounding surface so the repair does not flash under lamps.
For more repairs like this, start in the Water Damage & Stains hub. If you are working through a related problem next, see Water Damaged Wood Floor Repair (Easy DIY Restoration Steps) or Wood Floors from Dog Urine: Deep Cleaning and Restoration.
