Imagine several workshops selling surplus fabric while local designers look for material. Sellers post quantities and minimum prices; buyers post what they want and what they will pay. When compatible offers meet, a trade can happen. Nobody has to calculate a single price that satisfies everyone before exchange begins.
This is a double auction: offers come from both sides. Unlike an auction organized around one seller's object, it can support repeated trading among many participants. Repeated offers can coordinate information scattered across buyers and sellers, without everyone revealing their full circumstances.
A market needs participants
Suppose one workshop lowers its asking price after a week without a sale. A designer who previously waited now buys. Other participants see an opportunity to revise their own offers. Prices emerge through these adjustments rather than through a survey of everyone's private circumstances.
But a list of offers is not automatically a useful market. Fabric grades, collection arrangements, and quantities need to be comparable enough for an apparent match to mean something. With one large buyer and many desperate sellers, the ability to post a bid does not imply equal bargaining power. Thin participation can leave the page full of offers and almost no actual exchange.