Differences Between Natural and Lab Grown or Simulated Diamonds

What are the differences between natural diamonds and lab-grown or synthetic diamonds? For one, natural diamonds were born deep within the earth, billions of years ago. Natural diamonds are mined by an industry that supports 10 million workers and their families worldwide. Lab-grown diamonds, on the other hand, are created by using huge quantities of energy and are mass-produced in weeks in places like China and Singapore, where environmental standards are much lower than the rest of the world.

When buying a diamond the options are clear: the 'real thing'... or synthetic ones, also known as lab-grown, which have no lasting value. 
A diamond by definition is a mineral created by nature; a “diamond” always means a natural diamond. A synthetic diamond, by definition, is an artificial product that has essentially the same physical characteristics as a diamond. They are sometimes marketed as “laboratory-grown”, “cultured”, “created”, “cultivated”, “synthetic”, “simulated”, or “man-made”, but it's important to understand the differences.
Jewelry expert and writer Marion Fasel writes, "The lab grown gems hitting the market give the question a sense of urgency....What is a diamond? I have been giving the question a lot of thought lately with the abundance of lab grown diamonds hitting the market. A scientist will tell you a diamond is pure carbon. I believe it is much more."
In January 2018, nine leading international diamond and jewelry industry organizations agreed on a universally-accepted diamond definition. Their goal was to help consumers avoid confusion between natural diamonds and simulated ones, also known as synthetic or lab-grown diamonds.
"Synthetics or lab-grown diamonds are mass-produced in factories, made in a matter of weeks and primarily used for industrial purposes. None of these qualities is commonly associated with the rarity, beauty and luxury that embody a diamond," writes Jean-Marc Lieberherr in the Washington Post.