The question is only metaphorical tho, what are the ways to identify some physical “metals” from other ones ?
In: Chemistry
Density is probably the easiest.
You could check the hardness. Alkali and alkali earth metals tend to be really soft (and highly reactive, so it’s not likely you’d have a pure sample sitting in front of you.)
Then melting point. Most metals have a pretty high melting point, but a few are lower. (Mercury and Mercury’s safe cousin gallium.)
Color could be helpful if it’s not silver. (Few metals aren’t shiny and silver).
And then… if you had a galvanic cell you could do some plating and figure it out via the activity series.
It entirely depends on what tools you might have available. Just looking at color help with the obvious ones like gold and copper. You can estimate carbon content of steel with some spark tests. I believe you can probably recreate them with some kind of hard scraping implement.
Mercury, gallium, and other stuff like that that are liquid, or readily melt are obviously easier to tell apart. Lead, gold, and stuff like that are super soft and stuff too.
If you’re looking for a more specific answer, you’d need to be more specific about what kinds of metals you’re thinking of.
Also somethings aren’t magnetic, if that one wasn’t obvious.
Some easy nondestructive at-home indicators:
Density. Weigh it, submerge it in water, and find how dense it is. Compare this to an online density chart to narrow down your options.
Tap it on glass. This should make a noise, which with some experience can indicate a material.
Feel how much it bends – do not bend it too far as to permanently deform it, but enough that you get a sense of how flexible it is. Again, this can further narrow down your options.
Magnetism. See if it interacts with magnetism.
Nondestructive lab tests:
X-ray spectrometry. Blast it with x-rays, and measure the x-rays that return.
Conductivity. Measure how well it conducts electricity.
Thermal inertia/specific heat. Measure how much heat it takes to warm the object up, and compare that to a chart.
Destructive tests:
See how it reacts to heat. Color changes, sparks, flames, melting, and so on. Different metals have these properties.
Hardness. See what its hardness is by scratching it with different things.
Chemistry. See what can dissolve it, and what colors its solutions have.
Optical emission spectrometry. Put it in a glass tube and blast the hell out of it with electricity. See what colors it glows, and compare to known spectra.
Color, hardness and if a magnet is attracted to it are going to be the quickest and easiest way to get an answer for some metals. For example, if you’re not sure if it’s steel or aluminum, a magnet can answer that pretty quickly. After that, density and chemical reaction tests can be done with things found around the house. If you have a multimeter you can see how well it conducts electricity.
A lot of this is going to depend on what you’re trying to ID. Steel, SS, Aluminum, copper, lead are going to be a lot easier than some obscure metal or certain alloys.
The flame test. If you hold a sufficiently thin piece of metal over a flame then the colour of the flame can tell you what metal it is. (Copper burns green, iron burns yellow, magnesium burns white).
Some metals are not magnetic. (Copper, aluminium, zinc).
Each metal has a different melting point too. Eg. would be liquid at room temperature.
Without a microscope I’d use one or several of these criteria
Weight
Malleability
Magnetism
Conductance
Heat transfer
Melting point
And it should help me figure out which metal it is.
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