Solids, liquids and gases are all made up of very small particles called atoms. Each type of atom is given a name, and listed on the periodic table. Some solids, liquids or gasses are predominantly made up of only one type of atom. Common examples would be aluminum, carbon (diamond or graphite), and oxygen.

Gold is another material that is predominantly made up of only one type of atom, gold atoms. <

Pyrite is made up of a combination of Iron and Sulfur atoms bound together to form a compound (a compound is simply a combination of different atoms bound together).

Though pyrite looks somewhat like gold, it is made up of different atoms and has different properties. For example pyrite is less dense, harder, responds differently to heat and has a different color than gold.

Pyrite is Iron sulfide, chemical formula FeS. One of the quickest ways to tell that it is not really gold is to try to draw with it on a piece of rough porcelain. It looks lighter in color than real gold, although without any real gold to compare with, this is difficult to tell. However, if you look at its "streak" - that is, the color it writes when you draw with it on a "streak plate" - a piece of white, rough, porcelain, you are in for a surprise. It writes grayish-black instead of gold or yellow when you try to draw with it! This is one sure way to tell if you find pyrite in the field, when you can't weigh it and test its density.

Gold is an element made of gold atoms. It does not react easily with other elements. Like most metals it is rather soft and shiny.

Pyrite is made up of iron and sulfur and is one of the best known minerals that are named "Fool's Gold" because only a fool could believe they are gold! . Whether it is the golden look or something else, pyrite is a favorite among rock collectors. It can have a beautiful luster and it is so common in the earth's crust that it is found in almost every possible environment, hence it has a vast number of forms and varieties. Pyrite and Gold are easily distinguishable. Gold is much softer and much denser (gold is extremely heavy even for metallic minerals)and has a different color than pyrite. Pyrite is also more brittle and leaves a greenish black streak.

Pyrite is a mineral composed of iron and sulfur, which happens to have a yellow luster that can make it look like gold. Gold itself usually occurs a sa native element (ie. gold on its own with nothing else).

When you see the two together the gold has a really bright canary yellow color, while pyrite is a bronze sort of yellow. They often occur together, as gold is deposited in cracks in rocks by fluids (rocks contain microscopic amounts of water), that contain dissolved iron & sulfur.

I'm not sure how miners used to tell the difference, but I've heard that they would heat up the pyrite, which would turn the sulfur in it to hydrogen sulfide, which is also known as 'rotten egg gas', and very smelly! These days the pyrite/gold mix is heated in a furnace to high temperatures and dissolved in acid (gold does not dissolve in acid, while pyrite does).

Gold is a lot more dense than pyrite - it weighs about one and a half times more than pyrite.