Value Of KGV Definitives On Cover

I was wondering if someone with a GB specialized catalog could give me the values of these two definitives on cover. Thanks for your help.

A great deal of the cover's value would probably come from it being a zeppelin cover with zeppelin marks on it.

Understood. I'd like to know the values of the definitives on cover irrespective of the additional zeppelin cachet.

The penny value (SG419) is given by Stanley Gibbons as £1 and the nine pence value which is very likely to be SG427 as the postmark is 1932 and is priced by SG at £3.50.

The entire is probably valuable as it is uprated postal stationery with brilliant cancels and also has the Zep connection

Thank you, Scotzm. Much appreciated.

Gibbons don't give on-cover prices for stamps after Edward VII (1902-10, stamps issued up to 1913). However, the 1d stamp is extremely common (the £1 used price is basically a handling charge, 1p would be more realistic!). The 9d is scarcer but not too hard to find on-cover -- the SG catalogue price if there was one might be about £10-15.

GB usage material doesn't seem to be greatly collected, which keeps the price down. And this is a philatelic cover by a collector who prepared covers for practically everything they could think of! So an on-cover price wouldn't actually apply anyway. The value is in the Zeppelin usage, not the stamps.

On this particular cover the value of the stamps is irrelevant. The entire value is in it being a Zeppelin flown cover from a treaty state and it does not matter what the stamps are so long as they add up to the correct amount. One does not add the value of the stamps to the value of the flight when arriving at a price for such a cover. That would only apply in a case where extremely valuable stamps are used.