In 1993, the industry that was de-reserved was the mining of copper and zinc. This means that the government relaxed its control over this industry and allowed private players to participate and invest in it. The de-reservation of this industry was a significant step towards liberalization and opening up of the Indian economy.

The de-reservation of the mining of copper and zinc industry had several implications and benefits for the Indian economy:

Promotion of Private Investment:
- The de-reservation allowed private players to invest in the mining of copper and zinc industry, encouraging competition and promoting private sector participation.
- This led to increased investment in the industry, which resulted in technological advancements and improved productivity.

Economic Growth:
- The mining of copper and zinc industry plays a crucial role in the Indian economy as these minerals are essential for various industries like construction, manufacturing, and infrastructure development.
- With the de-reservation, the industry witnessed growth, leading to increased production and availability of these minerals, which in turn contributed to the overall economic growth of the country.

Job Creation:
- The de-reservation of the industry created employment opportunities as private players expanded their operations and hired more workforce.
- This helped in reducing unemployment and improving the livelihoods of people associated with the mining sector.

Efficiency and Competitiveness:
- Prior to the de-reservation, the mining of copper and zinc industry was largely controlled by government-owned companies.
- The entry of private players brought in market competition, leading to increased efficiency and competitiveness in the industry.
- Private players often bring in new technologies and management practices, which can result in improved productivity and cost-effectiveness.

Overall, the de-reservation of the mining of copper and zinc industry in 1993 was a significant step towards liberalization and opening up of the Indian economy. It promoted private investment, economic growth, job creation, and improved efficiency and competitiveness in the industry.