I was fortunate enough to travel with work to Brasiliana 2013, the international stamp exhibition in Rio de Janeiro. Although the show was a bit of disaster, in my free time (and there was a lot of it because there were so few visitors), I actually managed to find some nice Jubilee items in the exhibits.
Two exhibits 
listed immediately caught my eye. The first I headed for was “The Siege of Mafeking” by Antonio Cucchiani. The collection featured several rare covers with Jubilee frankings as well as an example of the double overprint on the 4d. The collection was awarded a Vermeil medal.
And the other was “The British Postal Service in the Levant, 1857-1923” by Alexios Papadopoulos. Jubilee items of note included three GB 1s green on a parcel label, one of only 3 known covers with the single ring cds of Salonica and the cover pictured adjacent which is one of only 3 recorded with the 12pi on 2s6d. Interestingly the collection did not contain a QV 4pi on 10d on cover. The collection was awarded a Large Vermeil.
Individual items of note included this 1/2d postal stationery card uprated with a 1/2d vermilion sent to Argentina and forwarded on arrival with an Argentinian stamp, which I just happened to spot in a collection of Argentinian postal history.
And this cover belonged to an exhibition entitled “Swedish Militaries & Volunteers in war, Campaigns or in active service abroad 1582-1905”. Certainly not an exhibition I would expect to find a Jubilee cover, but in fact this envelope was sent to a Swede attached to the 5th Dragoons in the British Field Army in South Africa, and had a long journey to try and find its addressee!
The 1887 Jubilee Issue 