At the moment, African medicinal plants are often ignored because foreign buyers have no guarantee of the quality of the materials they are purchasing.

ECONOMIST: A pharmacopoeia for Africa

But he also said he believed Iran is facing difficulty purchasing raw materials, particularly carbon fiber and maraging steel, it needs to produce this equipment.

WSJ: North Korea Nuclear Find Raises Fears It Will Share With Iran

In some cases, collective purchasing of raw materials can help reduce costs.

ECONOMIST: Italy's business clusters

The figures are based on a survey of purchasing executives who buy the raw materials for manufacturing at more than 350 industrial companies.

BBC: US manufacturing remains weak