I had to take a metallurgy nine week class for my job description many years ago and it's amazing how much I remember about metals. I never needed to use any of it for the job just had to be on paper I knew it. I remember it was fun tempering different metals in the workshops. I use to bend the metals in quilt block shapes and this was before I started to quilt. Seems everything relates to quilting to me in some form.

I leave mine open in a mason jar,I just shake a few out on the top as I need them , I havn't seemed to have problems.

The other side of that coin is ... do you really want pins that do not stick to a magnet. I would be lost without my big magnets for my pins? So glad I could tell you why "stainless steel " pins corrode...and all stainless is not created equal.