I have an interesting product configuration problem that seems to challenge most eCommerce engines.

I have a product, an earring, and the earring can come with one of two types of loop, a surgical steel loop or a sterling silver loop. There is only ever one earring.

I have been able to add the earring and give it the option of the loops. The loop type is selectable as a radio button.

The problem comes when I select a steel loop type and add it to the cart. I go back to the earring product and select the silver loop type and add that to the cart. And thats the problem. I shouldn't be able to add the earring to the cart twice as it is already added to the cart.

So that the problem. Has anyone seen or been able to resolve this product problem before?

Any configuration advice would be very welcome.

Thxs, Rob