SGC on centering

[irv]

Originally Posted by JollyElm

Can someone explain to me what in heck the reasoning is behind SGC's numerical grading system??

With PSA, a 7 is a 7 out of 10. Pretty simple and extremely straightforward. But an SGC 60 is only a 5? Even though 60 is higher than 50? An SGC 84 is a 7? Even though 84 is higher than 70? An SGC 98 is a 10?????? Why not an SGC 100 for that?????? Or, to follow their logic, a card rating a 10 should be something like SGC 115, right??? It makes no sense!!!!!!!!!!!!!!!!!!!!!

I know they have their 'weird' number on top with the 'real' number below it these days (and probably have had it there for quite some time), but what in high heck is their numbering system all about?????????????????

http://www.sgccard.com/GradingScale.aspx

[swarmee]

I think SGC's grading system is more of a percentage of mintness, rather than a 10 point scale with half grades. So a NM card is 84% mint, while a gem mint card is 98% mint, but a pristine card is 100% mint. At least that's how it seems to me.