group must buy a drink for the holder of the highest-ranking coin. A coin's rank is determined by the rank of the giver of the challenge coin. For example, a coin presented by an Admiral would outrank a coin presented by a Vice Admiral, while both would outrank a coin presented by a Captain. Traditionally, the presentation of a coin is passed during a handshake. Some units provide strict time limits to respond to a challenge. Also, coins are ranked in level of difficulty in attaining them. An Infantryman coin would outrank a logistical coin. A Ranger coin would outrank an Infantryman coin. Traditionally, rules of a challenge include a prohibition against defacing the coin, especially if it makes it easier to carry at all times. If the challenge coin is attached to a belt buckle or key ring or has had a hole drilled in it to attach to a lanyard, it no longer qualifies as a challenge coin. Appearance There are many finishes available—from a simple pewter to 24K gold. While there are only a few base metals, the patina (finish) can range from gold, silver, or nickel to brass, copper, or bronze—plus the antiqued variations. Soft or hard enamel or a printed inset with an epoxy coating may add color (the epoxies are often more resilient and scratch resistant than the metal surfaces). Cost Challenge coins are moderately inexpensive to design and produce. There are two basic processes by which to manufacture: zinc-alloy castings or die struck bronze. Zinc alloy castings offer the advantage of low cost. Zinc casting also allows more flexibility in design like cutouts found on spinner coins or bottle opener coins. While a die struck bronze or brass coin is more expensive, the result renders a far superior product (numismatic quality). , coins manufactured in China and South Korea typically cost between US $2.50 to US $7.00 per coin, depending on production process and complexity of design, laser engraving, enamels, voids, etc. The dies must be sculpted by an artist and can range in cost from US$50 to US$300, depending on complexity. The cost of domestic manufacture can be many times this amount. In order to be competitive, most North American companies offering challenge coins rely on having the product manufactured offshore. Many challenge coins are fabricated in South Korea, as the connection to the US military bases there is strong, and costs