SANTIAGO, April 7 (Reuters) - Chile's total lithium

resources are 28% greater than previously estimated, according

to new studies of salt flats in the northern Antofagasta region

that show a higher amount of the battery metal, state mining

body ENAMI said on Monday.

A new analysis shows that the La Isla salt flat holds 2.13

million metric tons of lithium, up 150% from a prior estimate,

while the Aguilar salt flat holds just under 1 million tons of

lithium, an increase of 40%, according to ENAMI.

Together, ENAMI said, they add 3.05 million tons of lithium

to Chile's total resources, which the U.S. Geological Survey had

previously estimated at 11 million tons.

Resources refer to the size of a mineral deposit, while

reserves refer to the amount that can be realistically and

economically mined.

According to USGS, Chile is the world's third-largest holder

of lithium resources, after Bolivia and Argentina, but is the

No. 1 holder of lithium reserves, with 9.3 million tons.

Chile is also the second-largest lithium producer globally,

with its Atacama salt flat providing output for state-run miner

SQM and U.S.-based Albemarle.

In May, ENAMI is set to choose a partner to jointly mine the

two salt flats studied as part of the Salares Altoandinos

project, which marks one of the state's first ventures into

lithium production.

ENAMI has received proposals from Chinese carmaker BYD

as well as miners Eramet, Posco

and Rio Tinto. CNGR Advanced Material Co

and LG Energy are vying to provide

financing.

The fresh data on resources is based on analysis from

external consultants that use ENAMI's exploration numbers.

"This confirms that Salares Altoandinos is a world-class

project," said ENAMI head Ivan Mlynarz.