22K Gold and 10K Gold
Wear Rating: 2-3
These platings are alloys of gold and other metals. They are much more durable than 24K gold, but will still eventually show wear. 22K Gold is the softest and least durable of these platings, but is only used for accent pieces that will recieve little wear.
Black Titanium
Wear Rating: 5
This plating uses Titanium oxide that is molecularly bonded to the metal pen components. Dark and stylish, this plating is very durable and will last for a lifetime while showing virtually no wear.
Chrome
Wear Rating: 4
Chrome plating is a cost effective alternative to the more durable, but more expensive Rhodium plating. This plating will still resist the normal wear and tear from ever-day use for many years.
Gunmetal
Wear Rating: 2
This black nickel plating looks much like the higher-end Black Titanium plating, but it is a much lower cost and less durable. Gunmetal plating is used only when Black Titanium plating is unavailable - e.g. Bolt Action pens.
Rhodium
Wear rating: 5
Possibly one of the world's most brilliant and durable precious metals, Rhodium is used by pen manufacturers all over the world to plate their finest pens. The elegant bright chrome finish will withstand a lifetime of use while showing virtually no wear.
Titanium Gold
Wear rating: 4.5
This plating is a rich, gold colored plating that will last many years. Titanium nitride that is color-matched to Gold is molecularly bonded to the metal pen components. The end result is an extremely durable plating that will virtually never show wear.
On the Durability of Platings
There is no way of telling how long these platings will last. The wearability rankings given to them are a general guide, but actual wearability will be largely determined by the usage, the environment where the pen is used, the body chemistry of the owner, and the care with which the pen is given. All of the platings I use will still provide several years of trouble-free service without showing wear.