A question arose on Pricescope about why an 8-8.5mm stud feels so much heavier than a 7.5mm stud.
Besides the volume increase, there is the issue of torque. Torque is rotational force. The farther a weight is from the axis of rotation, the greater the rotational force it exerts. Larger studs, being spheres, protrude outward from the earlobe farther than smaller ones do. Any increase in pearl diameter increases the distance of the farthest-most part of the pearl from the axis of rotation (i.e. the earlobe) and therefore increases torque.
Gravity pulls downward on all studs, but the rotational force is greater when the stud protrudes farther out from the ear. This is why larger spherical studs are much more likely to sag.
Button shaped pearls that are the same weight as a spherical pearl won't sag as much because the rotational force is less. Simple physics.
I also decided to move the thread from the Lowly Beaders Club to the Cultured Pearls forum, where it it more likely to be seen by the many visitors to Pearl-Guide.
Undoubtedly many people visit Pearl-Guide for the first time when they are considering buying pearls for themselves or for a gift, and what better time to learn that a small increase in millimeters of pearl diameter yields a large increase in the overall size of the pearl? Especially in the light of PSS (Pearl Shrinkage Syndrome)-- the fact that many of us want larger and larger pearls as time goes on.
I am not much on the science of pearls. I am a buyer/seller and have been for 49 years. How the size looks on the neck is the measure
of 7-8mm. When a person is viewing from 4-5 feet away 1mm is difficult or impossible to discern. 2mm is different. My dad always said if they are looking at reading distance from the neck the size difference is not on their mind.
Now I understand why we won the space race. In my 45-50 years of seling pearls I never would have given that a thought. Not useful in the selling situation but an amazing explanation. Certainly partially explains why natural pearls have .6mm hole to cultured whish is usually .8mm to 1.0m. Selling by weight. Not Volume but related. SUPER !!!!!