The Geneva deal under which Tehran agreed to curb its nuclear program sees sanctions eased on the key sectors of gold and precious metals, petrochemicals, car manufacturing and civil aviation.

Gold

Iran's gold reserves in September 2012 stood at 109 tons, according to the largest economic daily, Donya-e Eqtesad. It buys its gold mainly from Turkey and India.

Petrochemicals

Exports of products including PVC, polyethylene, ABS, polypropylene and polyester reached $5 billion (3.7 billion euros) between March and September 2013 and $12 billion for the Iranian year from March 2011 to March 2012, according to official figures.

Last year 22-27 percent of production was exported to China, 18 percent to the Middle East, 13 percent to India and just between 1 and 2 percent to Europe.

Before the Geneva deal was signed, Iran projected production of 50 million tons per year by March 2014, with 1.4 million tons for export.

The Mehr news agency said resumed exports to Europe of petrochemical products could bring in $2.5 million a year.

Car Manufacturing

Iran's second largest manufacturing sector after energy, according to industry experts, with up to 500,000 employees before the imposition of sanctions.

Production estimated at between 500,000 and 900,000 units, whereas in 2011, 1.6 million vehicles were built.

The main manufacturers are Iran Khodro and Saipa.

Civil Aviation

Iranian airlines, led by Iran Air, are under international sanctions including a U.S. embargo in force since 1995 on whole aircraft, spare parts and technical assistance.

The country's airliners are therefore among the world's most run-down.

Since 2010, they have not been able to refuel at main European airports.