Generally speaking, Buddha’s Relics appear in the ashes of eminent monk of Buddhism in China. The Buddha’s Relics is a kind of colorful round hard thing as big as soya bean, and can shine like gem. However, not every Buddhist monk has Buddha’s Relics after dying. It is said the Buddha’s Relics of some eminent monk can reach thousands, but other Buddha’s Relics look like a big egg. What a mysterious thing this is!
Perhaps you think Buddha’s Relics is a fictitious thing, but a lot of people see personally. We are sure that Buddha’s Relics isn’t calculus first. Because we have never found Buddha’s Relics in the calculus patient’s ashes, and the eminent monk’s body is very healthy. Maybe because the Buddhist monks are vegetarian, this causes a large number of fibers and mineral accumulation, form a certain crystalline solid finally. However, there are a lot of vegetarians in the world. Why isn’t there Buddha’s Relics in their ashes? This is a question that modern science can’t answer.
Only a person who reach Holy status or Buddha can produce relics. That is why people call relic as remnant from a Holy person.
There are science in Buddhism about how relic can appear only in person who already became a Buddha or Holy.
I do believe some early Christian monk or follower who already became Buddha, there are also some relics.