South Africa's economy grew at an annualised rate of 3.2 percent in the second quarter of this year, up from 2.7 percent in the first three months, the national data office said Tuesday.

A recovering mining sector was the greatest contributor to the improved quarter-on-quarter growth in Africa's economic powerhouse, contributing 1.5 percentage points, according to Statistics South Africa.

Real gross domestic product (GDP) grew three percent in the second quarter of 2012 compared to the same period in 2011.

Nominal GDP was estimated at 788 billion rands ($93 billion, 74 billion euros), the agency said.

Mining expanded by 31.2 percent in the period, compared to a 16.8-percent contraction in the first quarter, with platinum, diamond and coal contributors to growth.

Manufacturing shrank by 1.0 percent, however.

The International Monetary Fund has forecast 2.6 percent growth for the country for 2012 and 3.4 percent in 2013, while the central bank expects 2.7 percent and 3.8 percent for the same periods.

South Africa's economy grew by 3.1 percent in 2011.