Have you ever heard of the old trick to test if a gemstone is real by tying a strand of hair around it and lighting it on fire? The idea is that if the gemstone is real, the hair won't burn. While this might sound like a clever test, it's actually not a reliable way to determine the authenticity of a gemstone.
In fact, the science behind this test is quite interesting. Richard Hughes, a renowned gemologist and author of "Jade: A Gemologist's Guide," explains that hair will not burn when it's in contact with any crystalline material. However, if you wrap hair around glass, which is amorphous, it's poor thermal conductivity allows the hair to burn. This is because glass has a lower thermal conductivity than many other materials, which means it heats up faster.
But why doesn't the hair burn when it's in contact with a crystalline material like jade? The answer lies in thermal conductivity. Thermal conductivity refers to the ability of a material to conduct or transfer heat. Crystalline materials like jade have a high thermal conductivity, which means they are efficient at transferring heat. When the hair is in contact with jade, the heat from the flame is quickly transferred to the jade, and the hair doesn't have enough time to catch fire.
However, it's important to note that this test is not foolproof. Quartz, which is a very common simulant of jade, is also crystalline. This means that the hair won't burn if it's touching quartz either. So, the fact that the hair doesn't burn is not necessarily an indicator that the material is jade.
So, while the hair and fire test may seem like a fun and easy way to test the authenticity of a gemstone, it's not a reliable method. Gemologists and experts use a variety of other tests and tools to determine the authenticity of gemstones, including measuring refractive index, specific gravity, and conducting X-ray diffraction analysis.
In conclusion, the hair and fire test may be a popular trick, but it's not a reliable way to test the authenticity of a gemstone. The science behind it is interesting, but it's important to rely on more accurate methods when determining the authenticity of a gemstone.
