The Harappan civilization is referred to as a Bronze Age civilization.
Customarily, unalloyed copper was used for manufacturing artifacts and rarely tin was mixed with copper to make bronze.
Tools and weapons were simple in form. They comprised of flat -axes, chisels, arrowhead, spearheads, knives, saws, razors, and fish-hooks.
People also made copper and bronze vessels. They made small plates and weights of lead, and gold and silver jewelry of considerable sophistication.
The Harappans continued to use knives of chert blades. Further, a great skill and expertise have been seen in precious and semi-precious stone beads and weights.
Long barrel shaped cornelian beads (up to 10 cm. long) are the finest examples of craftsmanship.
Steatite was used for making a variety of objects like seals, beads, bracelets, buttons, vessels, etc. but its use in making faience (a form of glass) is particularly noteworthy.
The gold objects found in the form of beads, pendants, amulets, brooches, and other small ornaments in the Harappan civilization. The Harappan gold is of light color indicating high silver content.
Mature Harappan pottery represents a blend of the ceramic tradition of the pre-Harappan culture of both west of the Indus region as well as of the Saraswati area.
The pottery technology was quite advanced. Most of the pots were wheel-made.
Big storage jars were also produced. Pots were beautifully painted in black on the bright red surface with geometric designs, plants, animals, and a few paintings seem to depict scenes from stories.
More than 2,500 seals have been found. These are made of steatite. They mostly depict a single animal-unicorn bull, elephant, rhinoceros etc. but some also depict trees, semi-human, and human figurines; in some cases, participating in a ceremony.
Shell working was another flourishing industry. Artisans, settlements close to the sea manufactured shell ornaments like pendants, rings, bracelets, inlays, beads etc., besides objects as bowls, ladles, and gamesmen.
Intensive agricultural production and large-scale trade played significant roles in flourishing of the Harappan civilization.
The elegant social structure and the standard of living must have been achieved by a highly developed system of communication and a strong economy.
The trade must have been internal in the beginning i.e. between one zone and another.
Agricultural produce, industrial raw materials (including copper ores, stone, semi-precious shells, etc.) were traded on a large scale.
Besides the raw material, they used to trade −
Finished products of metals (pots and pans, weapon, etc.);
Precious and semi-precious stones (beads, pendants, amulets, etc.); and
Ornaments of gold and silver were also traded to various areas.
They procured −
Copper from Khetri mines of Rajasthan;
Chert blades from Rohri hills of Sindh;
Carnelian beads from Gujarat and Sindh;
Lead from south India;
Lapis-lazuli from Kashmir and Afghanistan;
Turquoise and jade from central Asia or Iran;
Amethyst from Maharashtra; and
Agate, chalcedony, and carnelian from Saurashtra.
The occurrence of mature Harappan seals and other artefacts in contemporary Mesopotamian civilization, and some of the Mesopotamian and Egyptian objects in Harappan civilization, and the evidence of Mesopotamian documents established that the Harappans had the trading relationship with each other.
The trade requires a regulation of exchange and of weights and measures.
Harappan weights and measures were cubical and spherical in shape and were made up of chert, jasper, and agate.
The system of weights proceeded in a series i.e.
first doubling, from 1, 2, 4, 8, to 64, then going to 160; then
Decimal multiples of sixteen, 320, 640, 1600, 6400 (1600 × 4), 8000 (1600 × 5) and 128,000 (i.e. 16000 × 8).
The tradition of 16 or its multiples continued in India till 1950s.
Sixteen chhatank made a ser (equivalent to one kilo) and 16 annas made one rupee.
The measure of length was based upon a foot of 37.6 cm. and a cubit of 51.8 to 53.6 cm.
Pictures of ships and boats are found on some seals and drawings on pottery from Harappa and Mohenjo Daro.
Ship or a boat, with a stick-impressed socket for the mast, has been found from Lothal.
The boats depicted on seals and pottery resembles with the boats used in Sindh and Punjab areas (even today).
For land transport, bullock-carts and pack animals like bull, camel, ass etc. were used.
The terracotta models of bullock-cart found on roads from various sites indicate that carts used in those days were of the same size and shape used in the present day.