Reston LloydCorelle Square 10-1/4-Inch Dinner Plate, Pure White, Pack of 6

Are they in unbreakable, did not see that in description ?

what material are the plates. . .original corelle?

Is the 10.25" the diagonal or the length of the side?

I just want to make sure they are solid white. In the middle of the plate says “six packs”. Nothing written on the plate right??