What's that spot on your child's new white T-shirt?
The remains of a chocolate ice-cream cone perhaps? Or the muddy aftermath of a skateboard stunt gone awry?
If you don't know the origins of a stain, all is not lost.
First, be patient. Zapping a drip, drop, or splat without zapping the fabric itself requires a gentle touch and the patience to repeat treatment until the blight is lifted.
These straightforward remedies for getting out unknown stains can help.
For unknown stains, a rinse or soak in cold water before treating is essential.
Get into the habit of checking wet clothes for stains before tossing them in the dryer, as this can permanently set a stain.
Unfortunately, you're not always near a washing machine or stain stick when a clothing disaster strikes.
Not to worry: Some remedies will work even on set-in spots and stains.
Mix one part of ammonia to eight portions of water. Apply directly on the stain, and let sit for 8 hours. Then wash the treated garment separately from the rest of your laundry.
Enzymes in laundry detergent help remove protein-based stains, such as blood and chocolate, and are often quite effective on unknown stains.
Add one teaspoon of a laundry detergent that contains enzymes to one cup of water. Work the solution into the stained area until fully saturated, and allow to sit for 10-15 minutes. Wash as usual in the warmest wash water temperature safe for the garment.
To make this stain treatment, mix one teaspoon dishwashing liquid and one cup water. Apply to the unknown stain. Allow to sit for 30 minutes, machine wash.
No mixing required here! Use 3 percent, undiluted hydrogen peroxide. Pour the hydrogen peroxide directly on the unknown stain. Use a toothbrush to work it into the fabric gently. Allow to sit for 5-10 minutes, then machine wash.
If, after all your efforts, that mystery spot is still visible, defer to the expertise of your dry cleaner. Professional chemicals can often dissolve greases and oils that detergents available to consumers can't.