I just read the Wiki article on calcium isotopes and it said the stable calcium isotopes such as 40Ca have never been observed to decay. Then, despite the high temperature of stars such as Sun there are calcium ions floating on the chromosphere of Sun. I thought calcium will be vaporized or even turned into plasma if it is exposed to extreme heat.
My main question is, is calcium for example 40Ca II is indestructible or at least can't be change to something different? If 40Ca II can indeed be change to something different like maybe carbon, helium, potassium, etc. what is the level of temperature that is required to achieve that?