Why did Kazakh people pierce their sons’ ears?

Both women who are fans of jewelry brands, and just girls who love jewelry, are probably unaware that in the history of mankind men were the first to wear jewelry. Men wearing jewelry on fashion catwalks is one thing as it is perceived as part of the image; another thing is when it is worn as part of an everyday outfit. However, initially, everything was different. So how did the first jewelry worn by men look like? Why did Kazakh people pierce their sons’ ears? Did nomads prefer gold or silver?