enow.com Web Search

Search results

  1. Results from the WOW.Com Content Network
  2. Gold plating - Wikipedia

    en.wikipedia.org/wiki/Gold_plating

    Gold plated - gold layer thickness greater than or equal to 0.5 micron; Heavy gold plated / Vermeil - gold layer thickness greater than or equal to 2.5 micron; Gold plated silver jewellery can still tarnish as the silver atoms diffuse into the gold layer, causing slow gradual fading of its color and eventually causing tarnishing of the surface ...

  3. Copper electroplating - Wikipedia

    en.wikipedia.org/wiki/Copper_electroplating

    Excluding the continuous strip plating industry, copper is the second most commonly-plated metal after nickel. [6] Copper electroplating offers a number of advantages over other plating processes, including low metal cost, high-conductivity and high-ductility bright finish, and high plating efficiency.

  4. Gold-filled jewelry - Wikipedia

    en.wikipedia.org/wiki/Gold-filled_jewelry

    If the gold layer is 10kt fineness, the minimum weight of the plated layer on an item stamped gold-filled marks according to the Federal Trade Commission (FTC) must equal at least 1 ⁄ 20th of the total weight of the item. If the gold layer is 12 kt or higher, the minimum layer of karat gold in an item stamped gold-filled marks must equal at ...

  5. Britannia metal - Wikipedia

    en.wikipedia.org/wiki/Britannia_metal

    For the first few years, [2] [9] [10] they were gold-plated bronze, then later (perhaps starting in the 1930s, [11] [12] [13] 1945, [14] or 1982/1983; [15] [16] [17] different sources disagree), they were made of britannia metal plated with copper then nickel silver then gold, except for three years during WWII, from 1942 to 1945, during which ...

  6. Gold bar - Wikipedia

    en.wikipedia.org/wiki/Gold_bar

    Additionally, the kilobar, weighing 1,000 grams (32.15 troy ounces), and the 100-troy-ounce (109.7-ounce; 6.9-pound; 3.1-kilogram) gold bar are popular for trading and investment due to their more manageable size and weight. [1] These bars carry a minimal premium over the spot price of gold, facilitating small transfers between banks and ...

  7. Plating - Wikipedia

    en.wikipedia.org/wiki/Plating

    Plating is a finishing process in which a metal is deposited on a surface. Plating has been done for hundreds of years; it is also critical for modern technology. Plating is used to decorate objects, for corrosion inhibition, to improve solderability, to harden, to improve wearability, to reduce friction, to improve paint adhesion, to alter conductivity, to improve IR reflectivity, for ...

  8. Fineness - Wikipedia

    en.wikipedia.org/wiki/Fineness

    For example, knowing that standard 18-carat yellow gold consists of 75% gold, 12.5% silver and the remaining 12.5% of copper (all by mass), the volume of pure gold in this alloy will be 60% since gold is much denser than the other metals used: 19.32 g/cm 3 for gold, 10.49 g/cm 3 for silver and 8.96 g/cm 3 for copper.

  9. Coinage metals - Wikipedia

    en.wikipedia.org/wiki/Coinage_metals

    Pre-1992 British pennies were made of 97% copper; but as of 2008, based on the price of copper, the value of a penny from this period is 1.5 new-pence. Modern British pennies are now made of copper-plated steel. Cupronickel, a base metal alloy with varying proportions of copper and nickel, was introduced as a cheaper alternative for silver in ...