Two metals, two behaviors
PT950 is 95 percent platinum with a small amount of another metal, usually iridium or ruthenium, for workability. White gold is gold alloyed with white metals and finished with rhodium plating.
Both look white. Platinum has a slightly grayer, denser tone; rhodium plated white gold is brighter and cooler, closer to chrome. Photographs rarely show the difference. Side by side under daylight, most people can see it.
The real comparison is not appearance. It is what happens to each metal over ten or twenty years of daily wear.
Weight and density
Platinum is dense. Its specific gravity is about 21.5, against roughly 15.5 for 18K white gold. A platinum ring of identical dimensions weighs close to 40 percent more.
That weight is the first thing people notice when they try one on. It sits differently on the hand and feels colder at first contact. Some wearers want that heft, and some find it heavy on a wide band.
Weight also affects cost, because metal is priced by the gram. The same design in platinum uses more grams and costs more per gram, so the metal line roughly doubles.
How each metal wears
Platinum does not lose material easily. When it is scratched or abraded, the metal displaces rather than flakes away, and the surface develops a matte gray patina. A jeweler can polish that back to a bright finish, and the ring gets thinner very slowly over decades.
White gold wears by losing its plating first. The rhodium layer thins at high-friction points, the warmer alloy shows through, and re-plating restores the white surface. Under the plating, white gold does abrade, and a thin band worn for twenty years will lose noticeable metal at the bottom of the shank.
For a 2mm band worn daily, platinum holds its dimensions longer. For a wide band, the difference matters less.
| Property | PT950 platinum | 14K white gold |
|---|---|---|
| Composition | 95% platinum, 5% iridium or ruthenium | 58.3% gold, white alloy |
| Specific gravity | About 21.5 | About 13.5 |
| Surface finish | Bare metal, develops patina | Rhodium plated |
| Maintenance | Polish to restore shine | Re-plate every 1 to 3 years |
| Repair | Welded with platinum, by a specialist | Easier for any bench jeweler |
| Relative cost | Highest | Moderate |
Prongs and stone security
Platinum prongs hold a stone well because the metal is strong and resists bending. When a platinum prong is pushed back into place, the metal work-hardens and stiffens.
White gold prongs are stiffer than platinum at the start but can fatigue. A prong that gets bent repeatedly will eventually crack, which is why prong checks matter more on white gold.
Neither metal guarantees a stone stays put. A tall setting on either metal is exposed to knocks, and the annual check is what prevents loss.
Resizing and repair
White gold is straightforward to resize. Most bench jewelers can size a band up or down within a day, and the solder color matches after polishing and re-plating.
Platinum requires a higher temperature and a different technique, and not every shop has the equipment. Sizing up is usually done by inserting a piece of the same alloy; sizing down means removing a section and welding the joint. The result is invisible when done well, and the work costs more.
Platinum also cannot be soldered with gold solder. A mixed repair shows a seam line and a color mismatch that only gets worse with polishing.
Skin reactions
Platinum is inert and among the least reactive jewelry metals. PT950 with an iridium or ruthenium alloy is a reasonable choice for someone with a history of reactions.
White gold depends on its alloy. Nickel-white-gold is common and nickel is the leading cause of jewelry contact dermatitis. Palladium-white-gold avoids nickel and costs more, and rhodium plating covers the surface until it wears at the edges.
Cost over time
Platinum costs more at purchase, often close to double the metal line for the same design. It carries lower maintenance cost: polishing as needed, no re-plating cycle, and no color drift.
White gold costs less up front and needs re-plating every one to three years. Over twenty years the maintenance adds up, though rarely enough to close the purchase gap on its own.
The honest framing is that platinum is bought for the next few decades and white gold for the next few years. Neither is wrong, and the choice usually comes down to how the ring will be worn.
Which to choose
- Daily-worn engagement ring kept for decades: platinum, for wear resistance and no plating cycle.
- Ring likely to be resized or repaired locally: white gold, for easier service.
- Budget-limited build where design matters more than metal: 14K white gold.
- Nickel sensitivity: platinum, or palladium white gold.
Both metals can be quoted against the same CAD model, so the price difference is a real number rather than an estimate. Start with the custom design service, or read the process page for how metal selection fits into the build. Care guidance for both metals sits in the learn section.