Flagstone Reinsurance Holdings, SA last night announced an estimated loss of $52.5 million from the New Zealand earthquake three weeks ago.

The quake, which measured 7.1 on the Richter scale, wrecked buildings, roads and rail lines in and around the city of Christchurch.

Flagstone's preliminary estimate is net of reinstatement premiums and retrocession and is based on its proprietary modelling analysis, the assessment of individual treaties and client data, third-party vendor models, and an estimated industry loss of $3.6 billion.

Flagstone CEO David Brown said: "As a global reinsurer, we expect to incur losses in international events such as this.

"However, as a result of our diversified portfolio, and based upon our current estimate, we expect to produce positive growth in book value per share for the quarter."

The class of 2005 reinsurer - one of a group that set up in Bermuda to take advantage of the the dislocation of the reinsurance market in the wake of Hurricane Katrina - is now based in Luxembourg, but maintains an operating platform in Bermuda.