Unless you are in the restaurant business, or the import business chances are no one ever told you about how to grade pine nuts. Grades for products are describe by the entire range of quality for a product, and the number of grades varies by commodity. There are eight grades for beef, and three each for chickens, eggs, and turkeys.

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On the other hand, there are 38 grades for cotton, and more than 312 fruit, vegetable, and specialty product standards. Given that there is an onslaught of wholesale pine nut venders and the price of pine nuts has risen greatly. There is a chance your seller might have been tempted to buy low quality pine nuts and pass them off cheaper than everyone else.

Pine nut sellers from overseas usually grade nuts per the number of kernels in 100 grams

600grains / 100g 650grains / 100g 700grains / 100g 750grains / 100g. Snow Pine Nut kernels 900grains / 100g 1100grains / 100g.
Here is another example:

A grade: 650pcs-750pcs/100gram
B grade:1100pcs-1200pcs/100gram
C grade:1500pcs-1700pcs/100gram

Pine nuts are quality can also be examined by purity. Some manufactures allow more impurities than others. I have seen up to 10% listed. The USDA does not have grades established for pine nuts, but I would anticipate that coming soon. I would look for "clean pine nuts" plump, with few broken kernels.

We took what was left of our inventory and graded it out by size, carefully inspecting for any broken kernels or impurities. We labeled our GREAT BIG pine nuts and they are the JUMBO of the Jumbos as grade AA and scaled down to size. Our smallest pine nuts are available for bird food and they are the lowest grade. While the USDA does not have established pine nut grades, we started our own based on sizing and sorting out the best of our pine nuts.