* Co sees higher than expected mill throughput due to soft ore
* CEO says this will lead to greater than expected gold output
* Revised preliminary economic assessment expected by end of Q2
TORONTO, April 19 (Reuters) - Canadian gold exploration company Rainy River Resources believes it has stumbled on to a whole new gold district in northern Ontario, where it is developing its flagship Rainy River project, Chief Executive Raymond Threlkeld said.
The project, located about 400 kilometers (250 miles) south of Goldcorp Inc's legendary Red Lake gold mine and roughly 200 kilometers west of Osisko Mining Corp's Hammond Reef gold project, has a very promising future ahead of it, Threlkeld said on Thursday.
Toronto-based Rainy River expects a soon to be released study on its namesake project to outline stronger production and processing numbers, along with some increases in capital costs.
"The ore is a little bit softer than we originally designed for, so it will allow a little bit more throughput. We were looking at 32,000 tonnes per day, but it could be as high as 35,000 tonnes per day," Threlkeld said.
"We think we might average (annually) closer to between 350,000 ounces and 375,000 ounces, versus the 329,000 ounces we are currently estimating on average over the life of mine."
The updated output and processing numbers will be part of a revised preliminary economic assessment that is set to be completed around the end of the second quarter.