Lab created diamonds have the exact same chemical, physical, and optical properties of natural earth grown diamonds, only they’re made with fancy tech in a science lab .
Forming a diamond requires carbon, heat and pressure. In natural diamonds, nature supplies heat and pressure. In a lab, the lab supplies the heat and pressure.
There are two types of lab created diamonds, CVD diamonds and HPHT diamonds. They're grown individually, and have its own personality, inclusions, color, everything. No two are exactly alike.
Lab created diamonds are graded with the 4C's from grading labs and GIA. This is why pricing fluctuates for it's unique qualities.
Mined diamonds consume more than 126 gallons of water per carat, and lab grown consume less than 20. Also mined diamonds produce more than 125 lbs. of carbon per carat, while lab grown produces less than 10 lbs.
Yes they cost less than mined BUT they are appraised exactly the same. So lab grown diamonds are an investment too.