Citrine is a variety of quartz crystal. Although natural citrine is pale yellow or pale orange, almost all citrine on the market today has been heat-treated. Heating produces colors from golden yellow, to orange, to dark orangy brown, and reddish brown. The darker colors are considered more valuable. Sources for citrine include Brazil, Bolivia, parts of Russia and Africa. Citrine is November’s birthstone. Citrine is also recommended for the 13th wedding anniversary as it signifies fidelity and bliss.