The following image is from a bas relief found in a "crypt" under a temple dedicated to Hathor in Dendrah, Egypt.
 

We (the ancient Egyptians) used the outline of shoulders and a necklace with three dots under as a symbol for gold jewellery.

This glyph has an upper part (neb) and a lower part, which was the subject of a lot of debates. Scholars agree on two thirds of the lower glyph due to its vast usage as fire. It is an arm with the palm facing up and a dark circle identical to that in the name of  [Ra'] centred below the arm. The problem is that the arm is at the center of the other two symbols, which make the possibilities extend from usage as a verb such as "smelting" to a noun such as "crucible". I go for "Furnace" because it combines them all. It is the device in which gold is smelted or purified, which could include a crucible and smelts and uses fire and is a furnace.

Else than "NB" (gold) we have three symbols arranged vertically, the first one under gold is the symbol of a copper vessel (copper cauldron) sometimes confused with granite vessels. This symbol was used since the old kingdom. Thus with a cauldron on fire placed after gold, it just means what it says.

We are certain that the picture is for a device made from copper and uses fire to do something with gold.

From there all we are doing is just adding our intelligent guessing.

We arrive at the inevitable fact that the temperature needed for boiling gold is too high to produce by primitive means, and the only alternative is to do it under low pressure. The top picture allows us to accept such an assumption as highly probable.

Another point is that melting gold for casting does not need such a complicated device at all. This device looks more like a reflux tilted column and it must be tilted for a good reason. The fire is under the return and not under the gold solid lump, which proves that the intention is to boil gold rather than melt it.

The last problem in this picture is, what happens to the gold that evaporates? The two hands inside the device are not part of it at all, they are part of the glyph that means "device". In other words, they do not resemble a construct in that shape but they symbolize a device placed there, or at least representing a specific action. My call is "condensation" (arms collecting the fruits), because that part of the vessel is where hot gold vapour meets the current falling down into the condenser. There the vapour loses temperature to the lower current and loses kinetic energy and is pulled down by gravity. If gold vapours lose enough energy before settling, they should arrive as nanoclusters. The trick here is using a very big vessel where time allows this to happen.

Of course gold was abundant to do that then, but now we experiment with samples, and we need an alternative way to do it, such as high voltage static charge causing colloidal dispersion or a similar function.

When hot gold vapour saturates the space inside the device the heat can just melt gold. Part of the vapour that causes the pressure is being cooled in the radiator section. When condensation takes place, a draft pulling the molecules in the direction of the radiator begins. Condensation continues and as the pressure drops more melted gold vaporizes to compensate. At a state of equilibrium the flow of heat energy is from the partial upper cycle to a "peal" (in the vapour elliptical orbit) down into the condenser, and the process becomes continuous.

I refrained from a very interesting explanation due to the structure of the raised arms inside the device. If the two arms were linked at the bottom by a squarish link it would have been the glyph of spirit.

It could have meant soul or essence, which is a very interesting meaning. Yet they looked more like the ones used in the glyphs of "device" so I went in that direction although I would have liked to give the other. In fact after I gave it a deep thought I do not find contradiction.

A device is a function and neither the construction nor the material. Like saying "a hammer" does not say what is it made of nor how does it look like. This makes a device close to the soul of the tool, which is its essence. So, this could lead us to believe that at that place the essence of the device function takes place, the formation of the gold spirit or the noble essence condensation. If you have a well-certified Hieroglyphic dictionary you can check that what I say is the ultimate truth.

One point that should be made too, is that that device is one in a set of devices. Gold was refluxed for purification from ore too (no condenser). A similar device (almost identical) was used for perfume extraction and had no low-pressure construction mechanism. The writing alongside the device shall confirm its application.

Regards,
Hemetis

[Editor's note: A couple of similar devices can be seen by clicking on this link.]