Parts of the coin design to be coloured are mapped with a digital camera . The precise parameters are transferred to the printer which applies a white primer and then coloured layers to the design . Coins undergoing this treatment are then cured overnight to ensure the eye-catching colours remain stable over time .
GILDED
Like colour , gilding applies a decorative layer on selected areas of a coin . In most cases , we electroplate a thin layer of 24-carat gold onto a silver coin . Electroplating works by electrolysis , which uses electricity to drive a chemical reaction .
The coin is dipped in gold based electrolyte solution . During the process , particles from a positively charged gold ‘ anode ’ are deposited on the negatively charged silver ‘ cathode ’ ( the exposed silver ). The duration of the electric current determines how many microns of gold are applied to the coin .
The Perth Mint has issued gilded coins since the 1990s . Today , gilded kookaburra , lunar , and koala coins , on which the animal is enhanced with a precision applied coat of fine gold , are among our most popular annual releases .
ANTIQUED deeper parts of the design black .
Finally , the coins are lacquered , protecting the surfaces from further change , and even allowing them to be handled safely with ungloved fingers .
Antiquing has had an enormous impact on creativity in modern numismatics . Proof , coloured , and gilded coins require a protective acrylic capsule to remain in pristine condition . To prevent such coins chaffing on the capsule , the rim must be the thickest part of the coin .
Antiqued coins are freed from these restraints , enabling our designers to explore collector themes in original and innovative ways , including three-dimensional inserts . Examples include the extraordinary Year of the Dragon Rotating Charm 2024 1oz Silver Antiqued Coin , and the equally remarkable Tears of the Moon 2021 2oz Silver Antiqued Coin .
AN ART IN ITSELF
There are many steps in the production of precious metal coins , including refining , blanking , image design , die making , striking , inspection , and packaging . Applying beautiful finishes is an art in itself – one that has been proved to have a significant effect on the way our superb releases resonate with collectors .
FEATURE ARTICLE
Antiquing was exclusively developed by The Perth Mint to give silver coins a unique look conveying the surface characteristics of an ancient artefact . It works particularly well when applied to coins celebrating themes from history and antiquity .
Struck pieces ready to be antiqued are immersed in warm oxidising solution to blacken the silver . Later in the process , the coin design is gently abraded to partially remove the dark patina from raised areas , leaving the
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