Swarovski and others crystals, rhinestones and flatbacks use PP, SS and MM, what do they mean and why!
PP means Pearl Plate and was originally used to measure, well Pearls. That’s because the pearls were graded through stacks of plates with varying size holes.
Pearl Plates are still Used
Actually we still use these in our first sort on sizes of our Murano Glass Beads. So if a bead/or stone is size PP 10 it will fall through larger plates but will stay in the PP10 and smaller. This helps us quickly sort through sizes of hundreds of beads – and obviously gives us a bit of range, which is why we always say “approximately”. And it would be virtually impossible for us to measure each bead with a micrometer.
SS means Stone Size and with the advent of better measuring equipmentm like bead gauges and micrometers, it has become the standard, just not as colorful history!!
Relative Sizes to Millimeters
They can all be converted to MM (Millimeters) and of course Inches and if you must, fractions!
Use our handy guide to understand or for reference.
Need the Exact Measurements?
I’ve been looking for a chart like this. Thanks! I printed it out. This is really helpful.