And in Mexico, the Oportunidades program decreased dropout rates between the 6th and 7th grade by 9 percentage points.

You'll typically notice less color while looking at the stone from the top down anyway (appraisers grade by looking at the side), and the metal of the setting further masks the tones.

By contrast, Anki estimates how soon you will next see the card right before you grade it (you are still supposed to grade by difficulty, but the dates are also right there for your consideration).