Theory:

People of the Indus Valley civilization make a living by selling various products and agriculture and hunting. The people of the Indus Valley were highly dependent on trade. Persia, Mesopotamia, and China were among the civilizations they interacted with. Some goods traded in huge quantities were terracotta pots, semi-precious beads, gold, silver, lapis lazuli, and coloured gems like turquoise, metals, flints, seashells, and pearls.
 
peals.jpg
Antiquities

There was proper foreign and internal trade (i.e.imports and exports) in the Indus valley civilization. The Indus people were able to spread their civilization and trade with many different far away lands thanks to various products trading. The Indus people can trade with civilizations near water thanks to the coastline and numerous rivers.
 
civilization near water.jpg
Trade in Indus valley civilisation
 
Standard weights and measures were used by the Indus Valley civilisation people daily in their business transactions. Harappan Civilization used a system of weights involving small stone cubes as a weighing object. Limestone and steatite are used to make these weights.
 
weights.jpeg
Weighing machine
 
The occupation of city workers includes things as pot making, bead making and cotton cloth manufacturing. Traders brought the raw materials workers needed and took away finished goods to trade in other cities.
 
a-sumerian-lapis-lazuli-uriraq.jpg
lapis lazuli
 
Terracotta pots, beads, gold and silver, coloured gemstones such as lapis lazuli and turquoise, flints, metals for making stone tools, seashells for shell ornaments, and pearls are some of the items traded.
 
shell indus.jpg
Shell Bangles
  
Minerals used by Indus people were imported from Afghanistan and Iran. Copper and Lead come from India. Jade comes from China, and cedar tree wood is floated from rivers of the Himalayas and Kashmir.
Reference:
https://bcindusvalleycivilization.weebly.com/uploads/2/6/0/8/26082606/2985618.jpg?272
https://bcindusvalleycivilization.weebly.com/uploads/2/6/0/8/26082606/8469394.jpg
https://images.squarespace-cdn.com/content/v1/59b94ccdcd0f6831fdd941ca/1510826828141-0G2FMPSIK46QVTPMAIB3/ke17ZwdGBToddI8pDm48kG87Sfbgg29A4BYEDq3OXvgUqsxRUqqbr1mOJYKfIPR7LoDQ9mXPOjoJoqy81S2I8N_N4V1vUb5AoIIIbLZhVYxCRW4BPu10St3TBAUQYVKcf4OxbJOyh_wHUnyc4kQLQ6SBshRGOku7c30Y_IRDNPta8R2IY5BHMaEj1zOWoDTZ/image-asset.jpeg