If not stated otherwise, the textures are licensed under the
CC Attribution 3.0 license (http://creativecommons.org/licenses/by/3.0/)

Author				  Work(s)
===============================================================================

Newton				- coal, earth, earth_dry, gold, ice3, ore,
					  rock, rocked_cracked, sand_rough, sulphur, tunnel, water
MimmoO				- ice2, brick
Nachtfalter			- acid, lava_red
Dustin Senos		- earth_rough
Andrew McConnochie	- granite
Ben Cloward			- snow1
Redwolf Design GmbH	- snow, lava
Pyrit				- sand_smooth

The following textures are licensed under the CC Attribution-Share Alike 3.0 Unported license (http://creativecommons.org/licenses/by-sa/3.0/)

texturepalace.com	- ashes (http://www.texturepalace.com/ash-wood-premium-and-free-stock-textures/)