The difference between Peugeot pepper mills and salt mills is in the mechanisms.
Pepper mills use durable hardened steel, for its exacting machining and long term performance. Case hardening is used; a tempering process that makes the grinding head as hard as a ball bearing. Peugeot pepper mill grinding mechanisms have two different size grooves: Channeling and Grinding. Channeling grooves (the larger ones) are designed to line up the peppercorns and to crack them. The Grinding grooves (the smaller ones) do the actual fine grinding process. The larger grooves are still individually hand cut into the mechanism using the techniques utilized in the 1842, when the mechanism was first created by Peugeot. Teeth in the grinding mechanism will not lock together, as in other mills, because the number of teeth are different on the grinding head and on the outer ring. This allows for the fine powder grind that is not available on other mills, and does not grind metal with the peppercorns, unlike most other mills. The durability of these mechanisms and their proven track record allows Peugeot to provide a lifetime guarantee on the grinding mechanisms, even when used commercially. Note that rust is not covered under this warranty; prevent rust by keeping the mill dry and don't use it for salt.
Salt mills (on the right) use a commercial grade of 18/10 stainless steel that is used in the chemical industry, to help keep the salt from corroding the grinder mechanism. Developed in 1995, the stainless mechanism in salt mills is guaranteed for 20 years.
Hardened steel vs. stainless steel. For pepper mills, hardened steel is preferred over stainless because of its greater hardness, and therefore its ability to maintain sharp burrs over a much longer period of time than stainless. Though hardened steel can rust, under normal use a pepper mill will not come in contact with water to make it rust. For salt, however, never use a hardened steel mill, since salt is highly corrosive.
Physical Vapor Deposition, or (PVD), is used to treat some mechanisms. PVD is a group of surface treatments at the atomic level that add surface protection and resistance to wear. The process is similar to electroplating, but without any chemical reaction, less hazardous materials and waste, and is thus more environmentally friendly.
PVD can be used on most metals, and even some plastics, and include treatment by the addition of metal oxides, nitrides, carbides and other such materials to the surface. In thin layers, PVD can replace some painting applications for decorative purposes. PVD is generally highly abrasion resistant, has a high temperature strength, and can be harder and last longer than hardened and stainless steels.
Filling - Remove top nut and cover to fill, then replace cover and nut. Turn mill upside down to get peppercorns or salt out of the mechanism, and turn top nut clockwise to tighten loosely. To grind, turn cover in a clockwise direction. (Never put moist salts in salt mills, or they will clog.)
The Grind - All mills are easily adjusted for different size grinds. Loosen top nut (counterclockwise) to obtain a coarser grind. To return to a finer grind, turn mill upside down and turn cover a bit (counterclockwise) to get peppercorns or salt out of the mechanism, then loosely tighten top nut to desired fineness. The closer the turning mechanism mechanism is to the base plate, the finer the grind.
Maintenance - Never wash your mill and never use a pepper mill for salt. Once in a while, place a drop of mineral oil on top nut. Wipe the wood or acrylic body with a moist cloth to keep it clean. If you don't intend to use the mill for an extended period of time, remove the peppercorns or salt.
Warranty - The lifetime warranty on pepper mills and 20-year warranty on salt mills covers defects in manufacturing of the mechanism only. Peugeot mechanisms are clearly identified by the name imprinted on the mechanism. It also covers the mechanism against wear. Keep the mills out of water, or the mechanism may rust and the wood may crack; neither rust nor wood degradation are covered under the warranty.
In 1810, the Peugeot brothers converted the mill inherited from their miller ancestors into a steel mill. Since then, rolled steel has been at the heart of Peugeot's activities. Saw blades and tools led to a wide and various range of manufactured products: from crinolines, sewing machines, shearers, penny-farthing bicycles and finally to cars. In 1840, the Peugeot coffee mill entered the kitchen and opened the way for the pepper mill in 1874. Since then many spices have felt the lion's claw.
Spices come in many varieties so they cannot all be ground with the same mechanism. For this reason, Peugeot has developed mechanisms with specific characteristics and designs, each adapted to a particular spice: pepper, sea salt, dry herbs, nutmeg, chili pepper, wet sea salt... Thanks to continuous innovation and the use of new materials, Peugeot now offers a very large range of mills. Traditional, electric or equipped with the patented U-Select grinding system, the Peugeot mill has become the industry standard.