From 1940 conditions in China made the centralised distribution of stamps for the whole country difficult. As certain values ran out, or new ones were required for rate changes, authority was given for obsolete or little used values to be surcharged. It is an interesting exercise to look at the various increases in rates (See Sieh and Blackburn ‘The Postage Rates of China’) and work out the use meant for the various surcharges — then find a cover showing this use. I've never seen it done but for those who like a challenge it would make an interesting club competition entry.
The 3c/5c surcharges (SG576-81) are still available in quantity mint and the more prominent varieties are listed by Gibbons. More are shown by Ma and Chan They are still not easy to complete used or on cover. The Kansu surcharge also occurs on water-marked stamps not uncommon and if you find a surcharge which does not appear in the catalogues you may have one of the 'bogus' types. These appeared at the time in Shanghai (See W.F. Jones in Stamps 1940) when news of issues from the far-flung provinces was hard to get and impossible to get officially confirmed.
The 7 c/8c surcharges are pretty straight forward. The key stamp is the Chekiang on 8c Dahtung with plain button (SG 620). I have still not managed to acquire one! In 1942 the 1c/˝c surcharges were produced. This was the first time the face-value had been increased by a surcharge, but presumably the ˝c. increase was not worth the attention of the forgers. I have not seen any anyway. The sub-types of the Hunan-Kwangtung surcharges are illustrated by Chan. With a clear head, a good light and patience it is possible to sort them out! A key point here is that it is best to accumulate a goodly number before trying. Being able to hold two stamps side by side enables you to separate by the colour of the red surcharge as well as the shapes of the characters and their spacings.
The 40c/50c are again pretty straight forward. One error which is listed by Chan but not Stanley Gibbons is on Yunnan where the top left character is different — well worth looking for.
The military post handstamps are not well studied and therefore of great interest to me. This series includes the first overprint on the 16c brown fifth sun. Look here particularly for the thin 16' variety. This applies to all the subsequent surcharges. SG do not list this variety, except for the basic stamp (why?) and Chan lists it for all of them. I am fairly sure that it will not be found on all the surcharges since it only occurred on certain plates of the basic stamp so I would not take Chan' s listing too literally. I am happy to be proved wrong of course and I look forward to the letter to the editor saying "I've got them all" (and illustrating them of course). The military post stamps are difficult to get used (I have a number cto with ordinary domestic cancels and a few with military post cancels which often include the FPO number in English), which appear cto. I have often thought that if one could accumulate enough one should be able to tie the FPO down to the province from this evidence alone. I have only one cover in my collection.
The 1942 "Domestic Postage Paid" surcharges (?) on 16c include some of the rarest stamps of China and some have been forged. Mint are uncommon, used very scarce and covers are rare. I have occasionally seen the re surcharge (see below) offered as the DPP where the resurcharge is faint. It should be noted that the perf. varieties listed by SG are not complete (for these and the 50c/16c and resurcharges). The sceptic in me says that some have been manufactured recently but so long as they do not command a great premium. . . . The papers vary too and perhaps the best way to collect them is to put them side by side. If it is different, you have added to the collection.
The 50c/16c are much easier to study with blocks and even sheets being available.
One probably needs to look at the various catalogues together to get a good listing, but even then new items can be discovered (see October '97 JCP for an example).
Covers here are scarce. The East Szechuan and Chungking GPO issues are often confused but can be told apart by the colour.
The 20c surcharges are the largest group and to me, fascinating. The mint ones, with a few exceptions, are readily available. There are numerous positional varieties which can occur on different basic stamps used by an individual province. Some sheets were overprinted in the original sheets of 200 and some in smaller sheets of 100 or 50 (or apparently 150 in one case). Details can be found in Ma and Chan. Of course the water-marked Martyrs mean you can collect the four watermark positions. I have not seen forgeries of the rarer examples of these stamps but it would not surprise me if they did turn up. Used examples are difficult to find and I have heard of very few, even those commissioned to order, being found while Covers are also rare.
Finally the DPP surcharges mentioned above were further surcharged 50c with two bars obliterating the original surcharge. Obviously varieties in the original surcharge can be found with the resurcharge.
There are many varieties not mentioned by Stanley Gibbons, or indeed Ma or Chan. In my collection there is the West Szechwan with the original surcharge omitted.
Fortunately I have a set in blocks of four which supposedly show all the types. I am not sure I necessarily agree with the previous owner’s attribution of the blocks to Ma numbers, but they do appear to be all different.
To summarise I find this a fascinating group of stamps. For the most part they are not too difficult to find, and being sufficiently complex, you can easily know more than will be known by the average dealer. If a general dealer gets a cover in his stock it is unlikely he will know how good it is.
You are unlikely to make a purchase like a colleague of mine who bought a small dragon (German China combination cover) based on the catalogue value of the stamps, but consider this. Most big China auctions have small dragon covers, but how many have a DPP cover or even a 20c. surcharge cover? My case rests.