No. Coke is mostly water which has a density of 1 g/ml. Gold alloys have a density of around 19 g/cm3.
the markings on jewellery to prove its white gold
yes
A platinum ring would have more of a monetary value than white gold. Though this is a personal choice on which ring you get.
A guess: the white "gold" contains a considerable amount of silver
I assume you are asking this for one of two reasons. First, because you have a yellow gold ring that you would like to make into a white gold ring. The answer to that is, no, you really can't do that. Liquid gold is molten, meaning that it is heated to a high enough temperature that it melts. Dipping a ring into molten gold would make it melt, too. Maybe not completely melt down into a puddle, but you would certainly lose any detail in the ring's design. The second reason you might be asking is because you have a "white gold" ring that has a golden yellow core, like yellow gold that has been dipped into white gold. This, unfortunately, is merely a brass ring (the yellow part) that has been plated with a white metal, perhaps white gold, but more likely some kind of whitish silvery base metal.
White gold
The symbols S51 on a 14k white gold ring illustrate the purity of the gold.
the markings on jewellery to prove its white gold
Yes can be white Gold hallmark in gold metal alloys Ring.
yes
You can get a white gold engagement ring at many online and high street retailers. The biggest misconception about white gold is that it is primarily made of yellow gold.
Yes can be white Gold hallmark in gold metal alloys Ring.
Gold clad (gold plated)
A platinum ring would have more of a monetary value than white gold. Though this is a personal choice on which ring you get.
White gold and diamonds
The WA ( World Archery Federation, former FITA ) targets are coloured as follows, from the inside out: * 9 ring, 10 ring and inner 10 ring - gold * 7 ring, 8 ring - red * 5 ring, 6 ring - blue * 3 ring, 4 ring - black * 1 ring, 2 ring - white
Yes, if it is brass