If you've bought shoes, torn into beef jerky, or taken certain medication recently, you have likely pulled out at least one tiny silica gel packet. After briefly wondering why your new backpack contained a warning-labeled squishy little pillow, you probably chucked it in the garbage with the rest of the packaging.

Yet those silica gel packets are as useful as they are ubiquitous, and you can give them a second, third, or fourth life instead of sending them directly to the landfill. But why are the tiny bags in so many products? And can you reuse them?

First, here's a bit of background on the silicone dioxide-based packets. The jewelry-like silica gel beads are a desiccant, a category of materials used to keep products dry by attracting water to their surface (meaning they adsorb, not absorb, moisture). Their moisture-wicking power makes silica gel packets immensely appealing to manufacturers, preventing water damage in products in transit or sitting on store shelves.

Although silica gel doesn't grow on trees, the porous mineral does come from the ground. Silica is harvested through a "straightforward" mining process using open pits or dredging, according to Robert Goodin, a mineral commodity specialist with the US Geological Survey's National Minerals Information Center. He says this usually removes vegetation and disturbs the ground's top layer. He adds that "on occasion, explosive charges will be used to break apart the rock."

"These little silica gel packets, they're in everything but [use in desiccation is] actually a very small percentage of what this industrial sand is used for," explained Goodin. "It's less than 1 percent of the eventual end use." He estimates that over 60 percent of silica sand —  similar to regular sand but with much more silica—goes to the oil and gas industry for fracking and other needs. Glass production uses up another roughly 10 percent.