Which gemstones that can withstand high heat without cracking? As in being boiled in water for 10 minutes or so.
I must share the standard disclaimer that I am not a doctor and cannot give out medical advice. Crystals for healing should be used as a compliment to other therapies and not as a replacement for regular medical care.
It is not the temperature so much as how fast you raise the temperature. Quartz can actually take a boiling temperature as long as you raise and cool the temperatures very slowly. Sudden temperature changes will stress the structure of the crystal causing stress cracks. A similar situation will happen if you take a cool stone and put it in direct hot sunlight or take a hot stone into a cooler temperature to quickly.
Master Crystal Healer
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