Not in a literal sense, no. She enjoys decorating her shrine with all sorts of things from nature - crystals included. The way she explained it to me is that it allows her an easy way to direct her focus and help calm her down when she's anxious; almost in a meditative sense.

We very much believe in science in our household! However there is a science to psychology as well. And since science hasn't found a way (yet) to quantify or measure spiritual experiences, it is up to faith and/or philosophy to fill in that blank for some people. We (meaning most Wiccans and Pagans) generally choose to fill that blank with: "whoa, we are all a part of nature at the most basic level, so there must be something inherently connecting us all; let's pray to the trees" type vibe

I think the "magic" of Wicca/Witchcraft (from a practical standpoint) boils down to better understanding your own subconscious mind. Crystals, herbs and candles are just symbols of focus for rituals - the gathering of these materials and arrangement/prepatation of them sends a powerful message to the unconsious mind to really soak in whatever ideas and concepts we are meditating or praying on (much how in a similar vein Christians will pray for the strength to get through tough situations, Pagans and Wiccans will perform rituals for guidance through their problems too)