Which Types Are These Stamps From Belgium ?

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Hello everyone !
I have these two stamps from Belgium and I would need help to identity which types are these stamps.

For the 10 cents brown, there's 4 types. One from 1850, one from 1851, one from 1858,and another one from 1854 (this one was printed with ribbed paper).

For the 20 cents blue, there's 4 types. One from 1850, one from 1851,one from 1858, and another one from 1854 (also printed with ribbed paper)

And I even heard that the types from 1858 got reprinted ! I don't have anything to check the watermark so can someone tell me which type is it ?
Thanks !
CS

You will need to check for a watermark to identify which Scott number you have IF it is the 1849-50 issue or 1851-54 issue. You can also measure the design and height of the oval. If the design is 17.5mm x 22mm with an oval that is 17.25mm high and the stamp is unwatermarked you have the 1861 issue. If the design is 18mm x 21mm and the oval is 16.5mm high and the stamp is unwatermarked you have the 1858 issue.

Thanks for help ! I'll check it out !