Human: How can I tell if a diamond is natural or synthetic? Assistant: 
The best way to tell if a diamond is natural or synthetic is by looking at the color and clarity of the stone. Natural diamonds are usually found in a range of colors, including yellow, brown, green, blue, pink, purple and black. Synthetic diamonds are usually more consistent in terms of color, ranging from white to yellowish-brown. Additionally, synthetic diamonds tend to have higher clarity ratings than natural diamonds.