The diamond color scale ranges from D to Z, D being colorless and Z being too saturated
What is a Colorless Diamond? - Gemone Diamond
4Cs of Diamonds for your Engagement Ring
Does White Gold Tarnish?
F&D, Guide to Diamond Grading
The 'Four Cs' that Determine a Diamond's Quality and Value - Diamond Buying School
Diamond Color
What Are D E F Color Diamonds?
Diamond Color Charts & Complete Guide - International Gem Society
What About Colorless Diamonds? Are They A Good Investment? - Diamond Investment & Intelligence Center
How Shape & Origin Increase Diamond Price