Diamonds are the most sparkling stones you'd have ever seen. This is not something anyone would want to argue about. These diamonds are too expensive for anyone but the richest to own. The major reason for their rarity is the process by which these gemstones are created through natural means.
It takes hundreds of millions of years and can only occur in specific places inside the earth's crust ensuring special conditions. Unlike the lab-manufactured diamonds, these diamonds are made by natural forces over many millions of years. Nowadays you can also buy lab-created diamonds. You can visit https://www.thebetterdiamond.com/ to buy lab grown diamonds in Singapore.
They are created so deep inside the earth, that the pressures and heat they are subjected to make it impossible for anything else to survive. The only way that humans can get to these natural gems is when they are brought to the earth's surface by volcanic eruptions.
However, lately, it has been very much possible to create man-made diamonds that replicate the real ones in all possible ways. Today's man-made diamonds are made with so much precision that only sophisticated chemical testing can tell the difference between them and real stones. If you evaluate the differences, you'll see that the natural diamonds do have tiny imperfections, while the man-made diamonds are perfect.
Another difference is the cost. It is known that these synthetic diamonds are much cheaper than the natural kind for obvious reasons. While the batch of lab-grown diamonds takes only a few months to be created while that of the natural sparkling gem takes millions of years.