.

[Arf]

I get a variety of sizes, shapes, patterns of seeds from different buds on the same plant.

Project begins stay tuned

[DenverJim]

interesting topic. I have found that seed color is related to plant color. I have some bluemoonshine, sunshine daydream, NL5, Pink and purple lotus, purple wookie seeds that are black, purple ,blue, purple specked, red specked and different shades of each. I think in general terms purple strains generally give a mellower high than green. Plus there are nice to look at.

[Only Ornamental]

The pericarp (aka seed hull or shell) is made out of tissue from the mother plant and hence may reflect certain traits from the mother such as high anthocyanidine content (i.e. purple colour). As you may know, some traits have a (co-)dominant or intermediate inheritance and could affect different parts of the plant. Extrapolating the offspring's traits from the seed's appearance may then be as accurate as just looking at the parents or rather it's way less than that but in cases where you only happen to have a seed without knowledge of its parents this kind of magic might be the only trick up your sleeve (that is, if you don't count growing out said seed as a trick ).
Some seed traits do correlate with certain plant traits due to in-/voluntary co-breeding versus evolutionary advantages but are only indicative for feral cannabis/hemp v.s. cultivated hemp and drug type cannabis. Most other stuff is likely hearsay and pothead fantasies no better than judging character by looking at someone's nose or fortune telling from lines of the hand.