Generally, materials are grouped into metals and non-metals.
To do your own specific gravity test for any type of metal, you'll need a few things first.
Room temperature (72ºF), water (distilled or reverse osmosis), a calibrated digital scale that measures a typical small metal sample sizes (preferably 1-200 grams capacity), a laboratory grade graduated cylinder, thread to suspend the sample in the water without touching the glass, and a specific gravity table to reference the result.
Record the weight from the scale. This is the mass.
To avoid mis-measurement, calibrate the scale. The laboratory grade glassware takes into account the meniscus formed by the water, but you have to level the glassware on a smooth surface and take the reading with both eyes at the same level as the meniscus.
Subtract the difference before/after introducing the metal to the water. This is the volume. Divide mass into volume and find where the value falls in the table. This is your specific gravity and preliminary material identification.