[Stifle]

Altered cards. If this hobby would adapt what jewelers do we wouldn't have this issue. Jewelry shops: 3 types of Diamonds that are sold as listed or we hope.
Fakes / Glass - Cubic Zirconia, not real diamond but attempts to be one and is listed as and sold as such. A very cheap version of the real thing.
Lab Created / Lab Grown - Basically a trimmed version of a card. The diamond is created with cut, clarity & carot. A altered version of a card in my opinion. The Lab Grown has the same minerals as earth found.
Earth produced Diamond - Roughly a Billion years of having the earth create what has to be searched and dug in order to be located. My opinion, the same as a un-altered card which is company produced.

There are buyers for each otherwise they wouldn't be available. What this hobby needs to do is have each card numbered like Edge use to do. Any card sent for grading that is a forgery needs to have a small forgery stamp on it by the grading company. A Altered card needs to be graded as "Altered" - Trimmed, colored, etc. These Altered cards need to be classified like Lab Grown Diamonds. Give the trimmers the same classification as what jeweler do with Lab Grown. Earth created diamonds have their own classification.

If we in this hobby would encourage graders to establish 3 categories of graded cards. This issue would be dealt with because each category of card would have its own value.

My opinion.