bluidragon,
Until Jeremy Shepherd comes along to reply to your other questions I can help a little.
1. About the price of earrings vs. strands. Earrings are actually not more expensive than strands of the same size and quality.
Here is an example-- the following hanadama 7.5-8.0mm strand is priced at $2140 for the 16 inch length, while the same size hanadama studs are priced at just $322.
strand:
https://www.pearlparadise.com/colle.../75-80-mm-white-hanadama-akoya-pearl-necklace
stud earrings:
https://www.pearlparadise.com/colle...s/75-80-mm-white-hanadama-pearl-stud-earrings
2. I think you are referring to Freshadama?
"Freshadama" is Pearl Paradise's trademarked name for their highest grade of
freshwater pearls. These are earring grade pearls that are drilled and strung as strands.
"Hanadama" is not any vendor's trademarked name; it refers solely to akoya (saltwater) pearls that have been certified by the Pearl Science Lab in Japan to have a particular grade of excellence when it comes to luster, nacre thickness, surface quality etc.
3. There is no internationally recognized grading system for pearls, unlike diamonds. Although most use the A-AAA system, you will see some vendors who use a A-AAAA system. Also, the meaning of each grade is determined by each vendor. (I saw some freshwater pearls at a bead shop yesterday that were decidedly mediocre in luster, and was told they were AAA.
Not! )
No pearls can be called Hanadama unless they have the certificate from the Pearl Science Lab.
Some sellers have excellent pearls that may be of hanadama quality but they have not sent the pearls to the lab in Japan for certification. I assume Mikimotos' very best stands are of hanadama quality even if they do not have the certificate.
But this is not necessarily true of other sellers. It is important to read each seller's own description of what their grades mean. And even then, some sellers may just buy better pearls than other sellers do, because their standards are higher, and one seller's AAA may therefore be better than another's AAA.
I'm going our on a limb here but I would say that one hanadama may be better than another hanadama. How can this be? A strand will be certified as hanadama if it meets certain minimum requirements. But some strands may exceed those minimum requirements.