Brass is not magnetic.
Brass is a metallic alloy derived from fusing zinc and copper. Zinc and copper do not have any magnetic properties themselves. The alloy they form which is brass also lacks any magnetic properties.
Both zinc and copper do not have unpaired electrons which are required for a metal to facilitate magnetism.
Magnetic Properties of Brass
Zinc and copper consist of filled completed orbitals. This means that both metals have no unpaired electrons. For a magnetic field to be present unpaired electrons are required.
These unpaired electrons align themselves by spinning in the same direction as an external magnetic field. This alignment is what results in attraction and by extension magnetism.
However, both zinc and copper are diamagnetic and fall on the opposite side of the magnetic scale. Diamagnetic is the typical setting of all materials.
The complete lack of unpaired electrons results in a slight repulsion when exposed to a magnetic field. Therefore, while brass is not magnetic it can still interact with the magnetic field by repelling it. The magnetic force is typically stronger so even though it repels the force it is still weak.
Can Brass become Magnetic?
Brass being a diamagnetic metal cannot be used to attract other magnetic metals. However, by changing its electronic configuration, you can make brass magnetic.
This is done by passing an electrical charge through the metal. You can achieve this by wrapping a copper wire across a brass piece. You then connect the Cooper wire to a battery. The electrical current will form a magnetic field thereby magnetizing the brass.
You can also use the brass for its diamagnetic properties by applying the Lenz effect. When an object is made from brass let’s say the balls of a pendulum swing.
In the presence of a strong magnetic field, the speed of the object is greatly reduced as the brass naturally repels. Adding traces of iron into the brass may allow it to be attracted to rare earth magnets.