INVESTMENTS

The Company invests in equity securities of silver and gold exploration and development companies. These investments are classified as available-for-sale and are measured at fair value in the financial statements with unrealized gains and losses recorded in Other comprehensive income (loss).



	At September 30, 2015
In thousands	Cost	Gross Unrealized Losses		Gross Unrealized Gains	Estimated Fair Value
Equity securities	3,730	(1,196	)	679	3,213



	At December 31, 2014
In thousands	Cost		Gross Unrealized Losses			Gross Unrealized Gains		Estimated Fair Value
Equity securities	$	5,687	$	(8	)	$	303	$	5,982

The following table summarizes the gross unrealized losses on equity securities for which other-than-temporary impairments have not been recognized and the fair values of those securities, aggregated by the length of time the individual securities have been in a continuous unrealized loss position, at September 30, 2015:



	Less than twelve months					Twelve months or more				Total
In thousands	Unrealized Losses			Fair Value		Unrealized Losses		Fair Value		Unrealized Losses			Fair Value
Equity securities	$	(1,196	)	$	1,017	$	—	$	—	$	(1,196	)	$	1,017

The Company performs a quarterly assessment on each of its equity securities with unrealized losses to determine if the security is other than temporarily impaired. The Company recorded pre-tax other-than-temporary impairment losses of $0.5 million and $1.1 million in the three months ended and $2.0 million and $4.6 million in the nine months ended September 30, 2015 and 2014, respectively, in Other, net.