T hat vintage Mickey Mouse money box to be offered by Greenslade Taylor Hunt in Taunton this week will appeal to collectors in three separate fields – and obviously that can only do its chances a power of good. You can be sure that even as you are reading this, Disney enthusiasts the world over will be perusing the GTH website.

They are a famously gung-ho group of people when it comes to pursing their quarry, and it's odds-on that the successful bidder will come from their number.

But over and above them, collectors of tinplate toys in general will be weighing it up. And then there are those who happily amass money boxes in all their forms – "all" being the operative word.

Ceramic piggies and boxes are the mainstay of the hobby – but apart from tinplate, you can add to the list of materials from which they are made everything from cast iron to silver, timber to plastic.

And even in the mainstream field of pottery you can be talking of a range that extends from porcelain to china, stoneware and earthenware.

Oddly, there's a serious explanation to why so many of us collected our pennies and threepenny bits in piggies when we were little. Pygg was the type of clay from which early banks were made – probably to store salt at first, back in medieval times.

We know that money was being saved in "pig banks" by the beginning of the 18th century, and the more user-friendly "piggy" trotted in as the years passed by.

These early banks had no hole in the bottom, meaning they had to be smashed when payback day dawned. Experts say they have found them dating back to the Dark Ages, about 500AD.

Among the big-name makers, Wade are best known for their family of NatWest Pigs, which were originally offered to children as an incentive to open and maintain a savings account. The core family of five, from baby Woody to dad Nathaniel, will sell for about £250, but there were also limited edition add-ons, and you might find yourself spending double that sum on Cousin Wesley alone.

All right, you can see all five regulars on the internet for £80-£100 – but pathetic and sad though it may sound, there's a thriving market in fake NatWest Pigs.

Other big British makers who had fun producing money boxes are Arthur Wood from the late Sixties, Masons from the middle years of the last century – and, of course, Wemyss, whose beautiful piggies bedecked in incongruous floral array are one of the great eccentric collectables of British antiques.

Wemyss produced its wares in Scotland up until the early Thirties, and while some of its smaller pigs are within reach of collectors on a budget of up to £1,000, in 2004 Sotheby's sold a graduated set of them for £70,000.

Not surprisingly, if somebody's prepared to fake a £10 NatWest Woody, they are going to go about forging £5,000 Wemyss pigs – so once again, it's buyer beware. But when was that ever anything but true in the world of collectables?