Which precious metal should you choose for an engagement or wedding ring? 14kt gold, 18kt gold or platinum 950?

The best choice is undoubtedly platinum. Platinum is remarkably durable, tough, white and pure, because platinum jewelry contains 95% pure platinum. That is simply striking, because with gold, for instance, it is practically impossible to make a ring from 95% pure gold — gold on its own is not hard enough. On top of that, platinum is hypoallergenic, which alongside everything else gives it a considerable advantage. A ring of 95% pure platinum will last for good, and it is precisely for that reason that we like to say it is a material that cannot be compared with others.

Platinum is, however, a rarer and heavier material than gold, which means platinum rings are roughly three times more expensive than rings in 14-carat gold, say. If platinum does not fit the budget you have set aside for a ring, our recommendation is 14-carat gold, because it is much harder than 18-carat gold — it contains a lower proportion of gold, so the ring is harder to scratch.

If you want a yellow or red ring, the choice is between 14-carat and 18-carat gold. As with white gold, we recommend 14-carat, because it is harder and so scratches and wears less.

What do carats actually mean?

The carat is a measure of gold's purity. You will see the mark 585 on 14-carat gold, and 750 on 18-carat gold. Those marks refer to the proportion of gold in the alloy.

We are often asked about jewelry: is that pure gold? The answer is simple — no. Pure gold, that is 24-carat gold (999.9), is exceptionally soft and unsuited to making jewelry. Pure gold is always mixed with other metals to achieve a particular hardness. A mixture of several metals is called an alloy.

When we speak of 14-carat gold, marked 585, that means the proportion of gold in the alloy is 58.5% (585); with 18-carat gold, the proportion is 75.0% (750).

The higher the carat, the closer the gold is to pure, which also means the softer it is. Almost pure platinum, on the other hand, has hardness and durability enough to be used in making jewelry.

Which material is worth more?

Platinum is the most valuable material, because platinum jewelry contains 95% pure platinum. On top of that it is a material rarer than gold, which gives it further value. After platinum in value comes 18-carat gold, because it holds a higher proportion of gold in the alloy than 14-carat does. And since the proportion of platinum in the alloy is 95%, a platinum ring will be the heaviest, just as an 18-carat ring will be heavier than a 14-carat one: the same ring will weigh 2.80 g in 14-carat gold, 3.40 g in 18-carat gold and 4.60 g in platinum.

Ring prices follow accordingly, from the highest for platinum to the lowest for 14-carat gold.

Is there a difference in color between 14kt gold, 18kt gold and platinum?

Where white rings are concerned, a platinum ring will be the whitest, because platinum's natural color is snow-white and it will never change. Between 18- and 14-carat white gold rings you will see no difference at first, because white gold rings are plated with a layer of rhodium. Once that layer comes away, that is once it wears off with use, an 18-carat gold ring will take on a faintly yellowish tint. A 14-carat gold ring will not yellow, because we use the whitest alloys on the market, but neither will it be as white as it was on the first day.

With a yellow gold ring, 18-carat gold will be a more intense yellow, precisely because of the higher proportion of gold in the alloy.