Color is determined by the amount of irritation the crystal was exposed to in its natural state. I have some rose quartz that is so pale it almost looks like regular quartz except for a pink tint. Topaz is the same way it can range from almost colorless to pale yellow to a bright stunning yellow-gold for Imperial Topaz. Imperial Topaz has a golden/orange color as compared to yellow which is a bright lemon yellow. Rose quartz can fade but the color can also intensify with the heat, it all depends on the crystal. Amethyst is notorious for fading, any sun will fade it. I have also seen Amethyst turn a muddy color from being in the sun, almost like a smokey color. Once again it depends on the crystal.
Master Crystal Healer
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