It was not the first time I saw a yellow cocoa nib. However, it was the first time I got interested. It was different from the rest as its color is pale yellow and its taste is not somewhere near to regular nibs. It is not bitter at all.
The occurrence is rare. It seems like a missing gold in a beach. You see it when you least expected. Perhaps it was an abnormality. If it was not, then, a white chocolate could be more real. Remember, commercial white chocolates are technically not chocolates as it contain no cocoa solids.
Seeds are fairly soft and white to a pale lavender color. They become violet or reddish brown during the drying process. The exception is rare varieties of white cacao, in which the seeds remain white. Historically, white cacao was cultivated by the Rama people of Nicaragua.(wiki)
Some of the beans are white, not the usual purple. Those from the Marañón Canyon are about 40 percent white.
White beans have fewer bitter anthocyanins, produce a more mellow-tasting, less acidic chocolate. They are mutations that happen when trees are left undisturbed for hundreds of years. According to Dr. Meinhardt. Telling which pod and which seed will have white color is impossible (Mr. Pearson).
Chocolate made from 100 percent white beans is extremely expensive. It is not related to commercial white chocolates. (nytimes.com)