Valued for their lustre and bright appearance, gold and brass are two metals used in manufacturing, jewelry, and other applications around the world. Though they may look similar, gold and brass are two distinctly different metals, and this article will help explain these differences, focusing on how to identify the two.
While some acids do react with gold, the vast majority of acids will not cause any reaction when coming into contact with gold, whereas brass is reactive with many acids. One way to test for gold is known as the acid test, wherein one puts a drop of nitric acid on the object being tested. If there is no reaction, then the object is pure gold, whereas other reactions usually signify gold plating or other substances like brass.
Another way to check whether an object is brass or gold is to see if there is a karat rating anywhere on the object. Some gold objects will have a karat rating signifying the object’s gold purity. Not all gold objects will have this, however.
Additionally, because gold is so dense, one way to test to see if an object is gold or brass is to weigh the object with the proper equipment and reference materials.
Yet another way to test the object is to scrape it against a ceramic surface. If the object leaves a gold streak, then it is pure gold, whereas a black streak generally signifies another substance.
If the price of the object is available, gold is in all cases far more expensive than brass.