Lace can be made from a variety of materials, some are synthetic. If it is not delicate, then wash as for the fiber it is made from. Old lace is difficult to wash without the risk of damaging it so if the article is valuable, consult a specialist cleaner. However, delicate lace can be soaked in plain distilled water for several hours to lift the grime.
Less fine or valuable lace can be washed in pure soap suds but avoid stretching and squeezing the lace as this can ruin its shape. Rinse well, then lay the lace out and blot with a towel.
Lace curtains can be folded and put inside a cotton pillow case for washing in pure soap suds.
