In auction practice a lot is the indivisible unit a bidder may purchase. It can be a single ring, a single stone, a parure, or a tray of mixed pieces gathered for one hammer price. Once a lot has been catalogued and assigned a number, its composition is fixed: the auctioneer will not sell a single bracelet out of a six-piece bracelet lot, and a buyer cannot decline part of a multi-item lot after winning it.

How lots are constructed

Composition is a deliberate cataloguing decision. A specialist will set important singles as their own lots, group secondary jewels by theme or period, and consolidate trade-grade material into wholesale lots that may run to dozens of pieces. The decision is informed by reserve, by expected demand, and by the practical cost of cataloguing each piece separately. At Christie's, Sotheby's and Bonhams the same jewel may be lotted very differently depending on whether it sits in a marquee evening sale, an online sale, or a jewellery and watches house sale.

Pre-sale identification

Each lot is identified by a lot number, a catalogue description, an estimate range, and, in jewellery sales, frequently a laboratory report. The lot number persists across the catalogue, the room display, the saleroom screens, the bidding paddle, and the post-sale invoice, and remains the legal identifier of the property after the sale until title transfers.

Lot integrity

Auction houses generally do not break lots between cataloguing and the hammer falling. If a lot is withdrawn it is removed in its entirety. Buyers should examine the full contents of a multi-item lot in person or have a trusted representative do so, as condition issues with a single secondary piece will not allow renegotiation of the price after sale.