Can Lab-grown Diamonds Replace The Real Thing?

Not really. Natural diamonds and lab-grown diamonds or synthetic diamonds have found their space and opportunity in the consumer market. Natural rubies, sapphires and emeralds have coexisted with synthetic or lab-grown rubies, sapphires and emeralds for decades and the same should be possible with diamonds. 

Useful link:

https://edition.cnn.com/style/article/lab-grown-diamonds-ethical-luxury-sept

Synthetics vs. Natural: The Battle Over Value

What makes a diamond valuable? The value of the diamond is built when you package it and brand it in the consumer's eye. The origin, whether it's mined or made doesn't guarantee a value.

Useful links:
https://www.diamondconference.ae
https://www.diamonds.net/News/NewsItem.aspx?ArticleID=64368&ArticleTitle=Synthetics%2bvs.%2bNatural%253a%2bThe%2bBattle%2bover%2bValue