Question about crazing of crockery

I have lovingly collected many Italian pottery dishes, such as deruta, and some that are unmarked but made in Umbria. They have a yellowish glaze and some handpainting. To my horror when I went to wash them, I noticed some of them have fine crazing all over that only becomes apparent when they are wet. The crazing is not detectable when the dishes are dry, it disappears. Consulting websites, I got conflicting advice. Many said to throw out crazed dishes. The websites on Italian pottery said that fine crazing is common and there is no problem in using them. I don't use these dishes often but I really don't want to throw them out especially when the crazing is not noticeable, except when you wash them. Any advice?

Contact Deruta and ask about their glaze components, just to make absolutely sure that they won't leach lead. I sure as hell wouldn't throw them out, though.

Thanks. Good idea.