engagement rings experts would never attempt to verify a diamonds color in a setting, and would insist on a certified color comparison before attempting to make a fair evaluation, confirming how difficult differences in color grades are to see.
The depression of the 1930s hit the diamonds trade hard. The cutting shops were sometimes shut down completely for several weeks at a time. The situation remained difficult until the outbreak of the Second World War.
Certified diamond jewelry tend to have fewer of these tiny imperfections than mainstream stones. The less diamond bracelet are ‘included’ the better they are able to reflect the light which passes through them, which intensifies ther’s beauty and fire.