Difficult questions: How much gold is in the sea?

Many people have tried and many have failed to find gold from the oceans.

In 1872, British chemist Edward Sonstadt published a report on the existence of gold in seawater . Since then, Sonstadt's discovery has inspired many people, from true scientists to scammers, to find ways to extract gold from this endless water.

Quantify sources of wealth from the oceans

Many researchers have tried to quantify the amount of gold in the sea. But to find the exact number is not easy, because the concentration of gold in the seawater is very low (it is estimated that for every part of gold there will be one trillion parts of water).

A study published in 1988 in Applied Geochemistry Magazine measured gold concentrations in seawater samples taken from the Pacific, giving the ratio of 0.03 per trillion. Previous studies found higher ratios, about 1 part per trillion.

This difference may be due to two reasons:

• One is in the collected water samples that have impurities.
• The second is technology limitations when machines in old studies are not sensitive enough to accurately measure the amount of gold in seawater.

Finding the exact number of gold in the sea is not easy.

Calculate the amount of gold

According to NOAA's National Ocean Service, Earth currently has about 333 million cubic miles of sea water. One cubic mile is equivalent to 4.17 * 109 cubic meters. Switching out, we will have 1.39 * 1018 cubic meters of water on the oceans. Meanwhile, the density of water is 1,000kg / cubic meter, meaning the Earth is carrying on itself 1.39 * 1021 kg of seawater.

Suppose 1) the concentration of gold in seawater is 1 part per trillion, 2) this concentration is the same in all waters, and 3) the concentration can be quantified, we can calculate the amount of gold in the ocean in the following way:

• A trillionth is equal to 1/1012.
• To calculate the amount of gold in the oceans, take the amount of sea water, ie 1.39 * 1021 kg as calculated above, divided by 1012.
• The result is 1.39 * 109 kg of gold.
• 1kg = 0.0011 tons, which means we can conclude that about 1.5 tons of gold are mixed in the water of the oceans.
• If done the same as above, but at a concentration of 0.03 trillion according to the most recent studies, the result would be 45 thousand tons of gold .

Measure the amount of gold in sea water

Because the amount of gold that exists in seawater is very small, not to mention that there are a lot of other impurities from the surrounding environment, seawater samples need to be treated before being analyzed.

Enrichment is the process of concentrating the trace of gold in the test samples, so that the achieved product is within the optimal range for most analytical methods. You can do the following:

• Remove water through the evaporation process, or by freezing water before making sublimation ice block achieved. However, this method will produce a large amount of residual salt, which should be separated from the concentrate product before analysis.
• Solvent extraction is a technique in which different components in a sample will be separated based on their solubility in different solvents.
• Adsorption technique , in which substances will bind to surfaces such as activated carbon. To apply this technique, the surface will be chemically modified so that only gold can adhere to it.
• Precipitate gold by allowing it to react with other compounds. This method will require additional processing steps to separate those substances from the gold-containing precipitate.

Gold is then separated from other substances or materials that co-exist in the water sample. Some suitable methods to use are filtration and centrifugation. After this process, we can find the amount of gold by applying techniques specifically for measuring substances at very low concentrations, including:

• Atomic absorption spectroscopy method, measuring the amount of energy that a sample absorbs at specific wavelengths. Each atom, including gold, absorbs energy at a specific wavelength set. The measured amount of energy is then converted to concentration by comparing it with known references.
• Inductively coupled plasma mass spectrometry, first the molecules are converted into ions, before being sorted by mass. The difference will then be compared with known references to infer concentration.

However, it must be remembered that even if there is a mass of gold dissolved in the water of the oceans, the cost of extracting this wealth from seawater may be even more expensive than the value obtained. OK.

• Find gold from technology waste
• 3 billion years ago in the ocean 10 times more than today