there is no marble factory in selangor if i not mistaken.
these factory just buy marbles / wood from supplier and assemble them in factory or keep stock .
furniture shop take stock from them.
the marble factory infact is in ipoh and langkawi(closed down)

i have seen vietnam white marbles, pretty white with sui qing on it.no yellowish and lines  if you know what i mean.
grade A marbles is 20mm thick while grade B/C is 18mm
Grade A is white, yellowish , reddish. if it is so clear, you can see thru the wood frame underneath at 20mm thickness

Grade B is darker , what i mean darker is the whole plate is darker. not just 1 spot
Grade C is darkest
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Grade A (notice you can see thru the frame)


Grade B

Grade C

i hope you guys will know how to differentiate when buying marbles next visit.