I've used WD40 to remove various stains. Works well on removing grease
from automotive work as well.. It may work for you, spray it on, scrub,
wash with soap.

-astria

Jerald Houk wrote:
Lemon Juice should do the trick.
It's the citrus acid in it that removes the stains.
I used to work with a lot of mahogany that turned my hands purple.
It works for me,
Jerry

"Clemens" wrote in message
...

I was picking and halving walnuts, and my hands got dark brown from
tannin in walnut's shell.

Please, is there any effective agent to remove dark stains off the
hands ?

I tried with acetone, alcohol, lighter fuel, paint thiner, windex,
washing soap, laundry detergent, but it didn't help.

Thank you.