This is not really very surprising as there are very many different terms in use, both in english & chinese that also overlap each other & certainly it can seem very complicated, especially to the novice collector.
With this guide I`m not going to try to explain the many different chinese terms used to describe decorative styles & techniques as I would need to write a book but will confine myself to the four western terms most commonly used & often misunderstood, that is the four "families" known by their french names as "famille verte", (green family), "famille rose", (pink family), "famille jaune", (yellow family) & "famille noire", (black family.)
As you might guess from the french words used these are western terms & are not used by chinese collectors & dealers, they were first used by Jesuits during the 18thC in an attempt to simplify & categorise the various colour palettes used on chinese porcelains of that era & the first thing to remember is that they should only be used when discussing 18thC porcelains, (or 17thC in the case of famille verte the oldest of the four families.) there are other terms to use when describing later 19th or 20thC pieces that I will mention later.
As mentioned above the oldest of the four families is "famille verte" or the green family which developed during the reign of the Kangxi emperor, (1662-1722) from the earlier "Wucai", (five colour) palette of the Ming dynasty. The five colours are red, green, yellow, blue & black upon a white ground ,although confusingly there may be less or more than five colours actually used. As the name implies various shades of green may be seen but the important thing to note is that the enamels of this period are thin & transluscent, there is no pink although there may be lighter shades of iron red used. One important point to remember when authenticating genuine famille verte pieces is that there will always be an irridescent halo around the blue enamel, this was caused by certain chemical reactions occuring during the multiple firings necessary to create a multi coloured piece of the time & generally is not seen on later porcelains.
"Famille Rose" or the pink family is probably the most famous of the four & also probably the most misused. It first appeared during the final years of the Kangxi reign, (around 1720) but very few pieces are that early & usually we would date famille rose from the reign of his son the Yongzheng emperor, (1722-1735.) As the name implies this palette is recognised by the use of rose or pink enamel & this was derived by the use of colloidal gold, (an import from the west which gave rise to the chinese name of "yangcai" or "falangcai" literally "foreign colours".) The enamels on famille rose pieces differ from those used on the earlier famille verte not only by the new colour but also by their opacity which was caused by the use of lead arsenic in the recipe.
One of the most common mistakes I see in ebay listings is where sellers see a preponderence of green for instance they call the piece famille verte, or if there is a lot of yellow it`s called famille jaune, the thing to remember is if the enamels are opaque & on a white ground even if there is only a tiny speck of pink enamel, (& gold being expensive there might not be much) the piece is famille rose.
The remaining two families you are much less likely to come across as most are fakes although sometimes genuine Kangxi porcelains may have been redecorated with black or yellow grounds during the late 19thC anyhow here`s a quick description of both. First "famille jaune" or the yellow family describes famille verte enamels on top of a yellow enamel ground, these are very rare as are "famille noire" or the black family pieces, introduced during the Kangxi reign which describes famille verte enamels on a black ground. The black ground was created by a translucent green enamel fired over dry black cobalt directly onto the biscuit creating a very dense black that is very different from the thick opaque black enamel of the 19thC.
So if these terms only apply to 18thC porcelains what do we call those wonderful multi coloured pieces from Jiaqing, (1796-1820) onwards? Personally if famille rose enamels are used on a white ground I prefer the chinese term "fencai" & if the enamels are on a coloured ground I think the best term to use is polychrome.
I`ve only touched upon what is quite a tricky & possibly confusing field, in another guide that I wrote a little while ago I recommended several books that I think you might find interesting & helpful. As well as these books for those looking for more information on chinese ceramics the "gotheborg" website is full of very good information & also has a very good glossary that can certainly help sellers be more accurate with their listings. For collectors there is also a gotheborg discussion group, (paid membership) as well as the Asian Arts forum which is free but less actively moderated & of course there`s ebays own antiques discussion group.