Ice-white platinum has long had enduring appeal in jewelry and experimental designers are now also turning to its lesser-known sister metals rhodium and ruthenium to produce work in darker hues. The deep gunmetal finish of Black Platinum/black rhodium plate and the pure black of ruthenium are both becoming increasingly popular. Platinum’s sister metals are produced mainly for industrial uses: rhodium as a component in automobile catalytic converters and ruthenium for electronics. Platinum black (Pt black) is a fine powder of platinum with good catalytic properties used for making hi-tec batteries and electrodes. It absorbs radiation. (1) But demand for jewelry, even though tiny when compared to the industrial market share, can add to the luster of a precious metal, especially as the exotic metals become more affordable. Both rhodium and ruthenium are much less expensive than they used to be, with rhodium currently just cheaper than platinum at $1,125 USD an ounce versus more than $10,000 an ounce back in 2008, and ruthenium at $48 an ounce, compared to $880 at its 2007 peak.
Black Platinum or Black Rhodium Plating is sometimes added to make your Jewelry “Pop.” It is not black as the name suggest rather it is a lustrous dark grey that can highlight the fine details that often fade into a shiny blur of the single toned pieces. It is as if a skilled artist has added shades and highlights to you design – it suddenly makes it look 3d and larger than life. “It’s a little bit more unusual,” jeweler Thomas Nayler said of black ruthenium. “I’ve used it before in bespoke pieces, when customers wanted a particular finish. It looks lovely – a glossy, polished black.”
“We have certain chainmail, one-off pieces coming into our collection, and we’ve been using variegated black rhodium on those, because it’s just coming into fashion now,” Jeweler Harriet Kelsal Kelsall said.
Rhodium
Rhodium is a very rare, naturally occurring member of the platinum group of metals – making it a very deluxe metal! Rhodium is actually one of the most expensive precious metals. The price of rhodium can fluctuate, but generally an ounce of rhodium can go for roughly $1,500 USD! It’s extremely tough, able to resist corrosion and scratches. It’s silvery color and highly reflective nature also make it “pop!” It is because of this toughness and highly reflective nature that rhodium makes an excellent plating material. Some people have health concerns about white rhodium that they do not have for the black. Rhodium is normally white, has been commonly used for years as plate to give a lustrous finish to white gold. Black platinum/rhodium is made by adding an ink dye that binds to the metal and also binds up the potentially hazardous qualities of pure rhodium. Platinum black The dark metal is as safe and comforting as it look.
What Exactly is Black Platinum/Rhodium Plating?
Jewelry plating is covering one metal surface with another. Rhodium’s extreme hardness and high melting point make it a difficult metal for jewelers to work, so pure rhodium jewelry is highly unusual. The Black Platinum/Rhodium makes engraving “Pop!” People that wanted a really different feel for their design were the first to celebrate with black rhodium. The visual effect makes things stand out. There’s just something so “rock n’ roll” and slightly misbehaving about it. I just love that! Diamonds glow as if on velvet when surrounded with Black Platinum. Black Platinum really sets off your gemstones. For instance if you wanted to set a pale opal, white diamonds would be too bright as an accent and overwhelm the subtle detail of the opal. Champagne diamonds would be best for this. However, if set in bright gold their delicate color tone would be overwhelmed and they would no longer looked champagne colored. The dark platinum creates a shade that will let the diamonds subtly glow and will still let the opal look like the star of the piece.
The black platinum looks is awesome as a plating but will wear off a bit more noticeably than white platinum/rhodium. This is especially true on rings that are worn daily and are simple, smooth and shiny. On detailed art pieces, like ours, the effect enhances the design as time goes on. So if you have a plain white gold shiny gold band you’re wearing that you’d like to spice up with black rhodium, that won’t fly well. I know that some jewelers like to sell spicing up a plain wedding band with a rhodium plating but the thing that helps make black platinum/rhodium “stick” to your jewelry is a textural element. If your ring design has engraving or some three dimensional texturing on it, then it is a good candidate for black platinum. Smooth rings don’t have anything for the rhodium to “hang on” to, so it will wear away faster. Most earrings and pendants are candidates for black platinum treatment because they don’t have to endure the frequent hand washing and the daily wear that rings go through. Fortunately, re-plating your jewelry is easily done if it starts wearing off your rings. On a smooth ring it is like waxing the smooth surface of your car. It looks amazing at first, but it does need maintenance to stay shiny and beautiful. And do not use acid or chemically reactive cleaner to clean any plated jewellery. as they work by taking the top layer (just a few microns) of the material away which will speed the thinning of your plating. Sonic cleaning is the best for these pieces
Black Platinum/Rhodium treatment will cost more than white rhodium. Because after the piece is plated, your jeweler will take the time to polish some of it away to create a bit more definition and lighter darker contrast. Any time your ring is sized, the black rhodium will need to be redone. Thus sizing a black rhodium finished ring will cost more. But, it is so worth it to have such a unique finish. A Black Platinum plating that has a sand blasted Matte Finish contrasting the shiny, adds depth and a subtle “difference.” This can work very well where the contrast between yellow gold and black platinum is too much. Black Platinum can make dated out of fashion pieces that you have had for a long time look up-to-date and interesting again. Black Platinum makes bespoke and one of art pieces (such as we have here at Spiritual Treasures) truly unique.
(Reporting by Jan Harvey; Editing by Veronica Brown, Peter Graff & Shé D’Montford)
Foot Notes
(1) The name of platinum black is due to its black color. Platinum Black is most commonly used for Polymer Electrolyte Fuel Cell (PEMFC), Microbial Fuel Cell, and Phosphoric Acid Fuel Cell applications (as the cathode catalyst or anode catalyst). It is also used as a recombination catalyst for hydrogen elimination. As such has been shown to stimulate plant growth. Platinum on Vulcan can also be used as a building block for sensor elements.
Historically many “self-lighting” gas lamps, ovens, and stove burners used platinum black to catalyze the oxidation of a small amount of gas, lighting the device without a match or spark. This works particularly well for producer gas, town gas, and wood gas which contain a substantial fraction of hydrogen gas (H2) which is particularly well catalyzed by platinum black. So black Platinum should not be worn near or in hyperbaric chambers or super oxygenated environments or spark risk environments.
Black Platinum is a key component used in personal radiation shields such as EMF Devices and technologies that claimed to combat and reduce the effects of environmental radiation, radio waves and damaging electromagnetic fields. It is interesting that black platinums readily absorbs radiation where as white rhodium emits low level radiation.
When PT Black dissolves it breaks down into platinum and O2
