What metals did the Harappans use?

The Harappans used several metals, including copper, bronze, gold, and silver. Copper and bronze were widely used to make tools, weapons, and ornaments. Bronze, an alloy of copper and tin, was particularly important for creating durable items like axes and needles. Gold and silver were primarily used for making jewelry and decorative items. The Harappans were skilled in metalworking, and their ability to craft intricate metal objects shows their advanced technology and craftsmanship.

This question related to Chapter 6 Social Science Class 6th NCERT.
From the Chapter 6. The Beginnings of Indian Civilisation.
Give answer according to your understanding.