Silica Gel Replacement? When you need a desiccant to absorb moisture
from packaged items such as photos, papers, ammunition or just about
anything you need to store dry, why not use something free that works
better than the expensive stuff? Silica Gel has been a staple for decades
but a free scrap of gypsum (sheet-rock) will work at least as well. Take a
piece of scrap gypsum board and cut it into manageable pieces (about 4” x
4” works for me.) Place the pieces in the oven at about 150°F for an hour.
This will dry out any moisture already absorbed. As soon as the pieces are
cool enough to handle, seal them into the storage container along with your
valuables. The gypsum will absorb amazing amounts of moisture and keep
your valuables dry.