Barbie's outfits were impeccably designed, and each was intended to have its appropriate shoes to complete it. Most collectors have a challenge in identifying all their loose shoes, and then matching them to the outfit. The reference books in my earlier blog post are a good source of information for this, as are several websites. I will start here by identifying vintage Barbie shoes, and describing how they are marked.
The most difficult type of Barbie shoe to be sure of is the open-toe shoes which came with the earliest vintage outfits in the 1960s. The shoes have a distinctive left and right shoe, and only the left shoe is marked "Japan"; the right shoe is unmarked. If you have any unmarked open-toe shoes, don't discard them as they may indeed be vintage. Once you get a feel for the quality of the plastic and the shaping of the sole, you will be able to distinguish Mattel from clone shoes. A very small number of open-toe shoes have a single hole in the sole to accommodate the base with prongs for the Number 1 Barbie who had holes in her feet. Shoes with two holes are all clone shoes and not by Mattel.
The next most common type of vintage shoe is the closed-toe pump, with both shoes marked "Japan" on the soles. In 1964/5, a very high heeled version, called “spikes” by collectors, was issued; after that they had a high, but slightly lower heel. Spikes are very sought after by collectors and command much higher prices than other closed-toe pumps.
Below: comparison of spikes and closed-toe pumps
Barbie's mod era outfits had a wider variety of shoes to reflect the rapidly-changing styles of women's shoes at that time. Pilgrims could be unmarked, or marked with Japan or Korea on the soles.
Squishy-bow shoes (so called because they are indeed lovely and squishy!) are probably my favourite mod shoe, because they easily fit over the stockings which are often part of the mod outfit, without damage to the stocking or the shoe.
Two other types of mod-era shoe are the T-strap and the square-toe shoes. The T-straps are marked Japan or Taiwan on both insoles.
Square-toe shoes are marked on both soles, although some are unmarked. They may be marked Japan, Korea, Hong Kong or Taiwan, reflecting the changing location of Mattels' factories in the early 1970s.
A useful resource to work out which open-toe and closed-toe shoes match which outfit can be found at: