Sierra Leone-focused African Minerals wracked up the bills in the first half, more than tripling its losses in the process.
The firm, which has also been hit by a particularly severe wet season in Sierra Leone, posted an operating loss for the period of $86.2m, mainly due to transaction costs and other professional fees.
This was up from $26.3m in the first half of 2011 and pushed losses per share wider to 26.2c, from 5.3c the previous year.
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The appalling weather had already forced the firm to production reduce its guidance for the year to between five and six million tonnes, compared to the eight previously stated.
The company's shares fell almost 8% in morning trading following the announcement.
African Minerals is a very big employer in Sierra Leone, a country with high unemployment, but has had industrial problems recently that led to one fatality.
In April, a protest by temporary workers recently laid off by the company's contractors, turned violent.
The company said the protest was used as a platform for anger over nationally high levels of unemployment.
That protest became a civil disturbance to which the police responded, resulting in the death.
In an attempt to improve employment relations in the country, the firm has appointed Graham Foyle-Twining as corporate Global head of Human Resources and Sustainable Development.
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