Bend the metal ore to determine its flexibility or breaking point. Soft metal ores that break easily are considered low-grade and are used in cheap production of home decor. High-grade ore does not bend or break easily and is used in appliances, electronics, jewelry and fuel manufacturing.
Determine where the ore was mined by examining the stamp or shipping information. For example, if you find a piece of ore that was mined in Australia in the Iron Knob area, then you are dealing with high-grade iron ore that has been developed by harvesting pure hematite. This area is rich in hematite rock and the iron content is higher.
Examine the inner workings of the ore through a microscope. Metal deposits vary in number throughout mineral ore composition. A higher number of crystal formations within the ore indicates a higher-grade ore while scattered, few crystal formations indicate low-grade ore.
Melt the ore in a Bunsen burner. Adjust the temperature periodically, closely observing at which point the ore begins to soften and melt. Higher temperature melting points above 900 degrees Fahrenheit are required to melt high-grade ores while lower temperatures from 550 to 650 degrees Fahrenheit are the melting point for low-grade ore. Bunsen burners can reach temperatures of up to 1200 degrees Fahrenheit.