2.	Intangible and Other Assets

Following is a summary of intangible assets as of December 31:

		2016				2015
	Weighted Average Life	Gross Amount		Accumulated Amortization		Gross Amount		Accumulated Amortization
Intangibles:
Patents and licenses, software and hardware designs	6 years	$	5,033	$	3,187	$	4,754	$	2,839
Developed technology	10 years		2,782		2,017		2,782		1,739
Customer relationships and non-compete	9 years		2,838		2,331		2,838		2,042
		$	10,653	$	7,535	$	10,374	$	6,620

Amortization expense for 2016, 2015 and 2014 was $915, $1,235 and $1,313, respectively. Estimated amortization expense for each of the ensuing years through December 31, 2021 is $638, $565, $279, $17 and $0, respectively.

Following is a summary of other assets as of December 31:

	2016		2015
Other assets:
Bauxite raw materials:
Inventories	$	3,989	$	4,145
Other assets		1,524		1,962
	$	5,513	$	6,107

Bauxite raw materials are used in the production of heavyweight ceramic products. As of December 31, 2016 and 2015, the Company has classified as long-term assets those bauxite raw materials inventories that are not expected to be consumed in production during the upcoming twelve month period. For additional information, refer to Note 4 – Impairment of Long-Lived Assets.