Jack Dykinga / Scalding hot water continuously spouting behind layers of mineral deposits, Fly Geyser, Black Rock Desert, Great Basin Desert, Nevada, USA

Yva Momatiuk & John Eastcott / Minden / Calcium tufa formations, Mono Lake, California

Milan Radisics / Crystallised patterns in an abandoned pond used for the disposal and stacking of phosphogypsum with shallow, but highly toxic radioactive green water in Huelva, Southern Spain. Phosphogypsum is a radi...

Milan Radisics / Service road crossing an abandoned pond used for the disposal and stacking of phosphogypsum with crystallised patterns and shallow, but highly toxic radioactive green water in Huelva, Southern Spain....

Milan Radisics / Service road crossing an abandoned pond used for the disposal and stacking of phosphogypsum with crystallised patterns and shallow, but highly toxic radioactive green water in Huelva, Southern Spain....

Milan Radisics / Aerial shot of yellow mineral sediments flowing into the Atlantic Ocean, near Stokkseyri, Southern Iceland, August 2018.

Milan Radisics / Aerial shot of the Austurfljot glacial river, southern Iceland, August 2018.

Milan Radisics / Aerial shot of the Austurfljot glacial river, southern Iceland, August 2018.

Milan Radisics / Aerial shot of the Hafursa glacial river running over black sand, southern Iceland, August 2018.

Milan Radisics / Aerial shot of steam geysers at Gunnhuver Hot Springs, Reykjanes Peninsula, Iceland, August 2018.

Milan Radisics / Aerial shot of Gunnuhver steam geyser, Gunnhuver Hot Springs, Reykjanes Peninsula, Iceland, August 2018.

Milan Radisics / Aerial shot of Thjorsa glacial river, southern Iceland, August 2018.

Milan Radisics / Aerial shot of Thjorsa glacial river, southern Iceland, August 2018.

Milan Radisics / Aerial shot of Kudafljot glacial river flowing over black volcanic soil, Iceland, August 2018.

Milan Radisics / Aerial shot of Kudafljot glacial river flowing over black volcanic soil, Iceland, August 2018.

Milan Radisics / Aerial shot of a confluence of three tributaries flowing over black sand at the mouth of the Affall River, Landeyjar area, Southern Iceland, August 2018.

Milan Radisics / Aerial shot of the estuary of the Holmsa and Kudafljot glacial rivers, Grafarkirkja, Iceland, August 2018.

Jack Dykinga / Navajo Sandstone formations with striated lines of mineral deposits. Grand Staircase-Escalante National Monument, Utah

Lucas Bustamante / Scarlet Macaws (Ara macao) drinking water inside an Amazonian claylick. Yasuni National Park, Orellana, Ecuador

Guy Edwardes / Landscape of Alpe di Siusi, Dolomites, Italy, March 2016.

Nick Garbutt / Red-and-green macaw (Ara chloropterus) flock flying in front of clay lick. Heath River, Tambopata / Bahuaja-Sonene Reserves, Amazonia, Peru / Bolivia border.

Anup Shah / African elephants (Loxodonta africana) feeding on loose soil for its minerals, Maasai Mara National Reserve, Kenya. Taken with remote wide angle camera.

Anup Shah / African elephants (Loxodonta africana) family herd feeding on loose soil for its minerals, with dramatic stormy skies behind, Maasai Mara National Reserve, Kenya. Taken with remote wide angle camera.

Anup Shah / African elephants (Loxodonta africana) family herd feeding on loose soil for its minerals, with dramatic stormy skies behind, Maasai Mara National Reserve, Kenya. Taken with remote wide angle camera.

Lucas Bustamante / Scarlet macaws (Ara macao) and Red and green macaws (Ara chloroptera) at clay lick close to the Tambopata river. Tambopata Reserve, Madre de Dios, Peru.

Eric Baccega / Dallol hot spring with salt concretions coloured by sulphur, potassium and iron, Dallol Volcano, Danakil Depression, Ethiopia, March 2015.

Eric Baccega / Dallol hot spring with salt concretions coloured by sulphur, potassium and iron, Dallol Volcano, Danakil Depression, Ethiopia, March 2015.

Eric Baccega / Afar men mining salt at Lake Assale. Danakil depression, Afar region, Ethiopia, March 2015.

Eric Baccega / Salt caravans made up of hundreds of Dromedary camels (Camelus dromedarius) and their pullers transporting salt slabs cut from Lake Assale to the Mekele Market, Danakil depression, Afar region, Ethiop...

Eric Baccega / Salt caravans made up of hundreds of Dromedary camels (Camelus dromedarius) and their pullers transporting salt slabs cut from Lake Assale to the Mekele Market, Danakil depression, Afar region, Ethiop...

Jean E. Roche / Aerial view of Salin de Giraud, Camargue, France, July.

Jean E. Roche / Aerial view of Salin de Giraud, Camargue, France, July.

John Cancalosi / Brazilian agate, slice, with MR. Sad Face design.

Enrique Lopez-Tapia / Graphite mine near the Andasibe-Mantadia National Park, one of the environmental problems affecting the ecosystem of the rainforest. Madagascar, March 2005.

Jabruson Motion / Two male African Forest elephants (Loxodonta cyclotis) play fighting at a mineral hole, Dzanga Bai, Dzanga-Ndoki National Park, Sangha-Mbaere Prefecture, Central African Republic.

Jabruson Motion / Two male African forest elephants (Loxodonta cyclotis) greeting each other at a mineral dig, Dzanga Bai, Dzanga-Ndoki National Park, Sangha-Mbaere Prefecture, Central African Republic.

Jabruson Motion / Group of African Forest elephants (Loxodonta cyclotis) feeding at a mineral hole, Dzanga Bai, Dzanga-Ndoki National Park, Sangha-Mbaere Prefecture, Central African Republic.

Jabruson Motion / Female African forest elephant (Loxodonta cyclotis) at a mineral dig with a baby with an injured leg, chasing other adolescent elephants away, Dzanga Bai, Daznga-Ndoki National Park, Sangha-Mbaere Pre...

Jabruson Motion / Baby African forest elephant (Loxodonta cyclotis) with an injured leg at a mineral hole, pushed away by an adult female, Dzanga Bai, Daznga-Ndoki National Park, Sangha-Mbaere Prefecture, Central Afric...

John Cancalosi / Cross-Section of Utah Septarian Nodule, Utah. A type of geode, Utah Septarian Nodules are found about 15 miles east of Zion National park. They were formed in an ancient sea floor during the Cretaceou...

Jouan Rius / Petrified wood segment, Blue Mesa Badlands, Petrified Forest National Park, Arizona, USA, December 2012.

Jouan Rius / Gypsum sand dune at sunset, White Sands National Park, Chihuahuan Desert, New Mexico, USA, December 2012.

Jack Dykinga / White Sands National Park with its white gypsum dunes dotted with Yuccas (Yucca elata) creating patterns amid the dunes. White Sands, New Mexico, USA. January 2013

Adrian Davies / Fossilised fly in Baltic amber. Whole specimen approx 15mm long. Fly approx 5mm.

Floris van Breugel / Various fluorescent minerals : 1Willemite, New Jersey, 2: Willemite and Calcite, New Jersey, 3: Fluorite, Ohio, 4: Willemite and Calcite, New Jersey. 5: Fluorite, California. 6: Scheelite, California....

Jabruson Motion / African forest elephant (Loxodonta africana cyclotis) calf keeping larger juvenile from gaining access to a mineral dig, Zanga-Ndoki National Park, Sangha-Mbaere Prefecture, Central African Republic

Jabruson Motion / Female African forest elephant (Loxodonta africana cyclotis) and calf kneeling and drinking from mineral pool, Zanga-Ndoki National Park, Sangha-Mbaere Prefecture, Central African Republic

Jabruson Motion / Small group of African forest elephants (Loxodonta africana cuclotis) running into forest clearing, trumpeting to dominant male feeding and cooling down in a mineral pool, Dzanga Bai, Dzanga-Ndoki Nat...