Another type of cachet used less frequently than open cachet is known as a "Zee'ch," or "search" cachet. In a Zee'ch transaction, the seller seals the stone and signs the parcel. This signals his agreement not to show the stone to anybody else for a period of twenty-four hours. A Zee'ch seal does not give the buyer an option to purchase the sealed stone at a particular price. Rather, it gives him an exclusive right to resume negotiations for the stone at a specified time in the future. It is common for buyers to shop around by putting a variety of stones under Zee'ch. This practice makes sense in the market for rough stones where no standardized price information is available; it makes comparison shopping easier, which facilitates competitive pricing.

Lisa Bernestein, Opting out of the Legal Sys…, loc. 61