They are all officially emitted, but as you might have noticed, they are all for airmail.
I can't tell you if these stamps have actually been used for sending letter. The structure of the stamp (plastic) isn't really ment for cancelling, and besides of that, the stamps are quite big too. Machines that process letters nowadays, might rip off the stamps when such letters are passing through.
The sets I have (and I don't have them all !) are available for fair prices, in MNH-condition, but I doubt if they can be found postally used. If so, they are rare.
In my previous post, I have shown some of the 1971 and 1972 issues.
1972 was indeed a year with almost alone 3D stamps. And since I have recently purchased some of those sets, I'm sharing some more with you today.
|Umm-al-Qiwain - dogs (1972)|
|Umm-al-Qiwain - flowers (1972)|
|Umm-al-Qiwain - butterflies (1972)|