The Hatrurim Formation or Mottled Zone is a

geologic formation A geological formation, or simply formation, is a body of rock having a consistent set of physical characteristics ( lithology) that distinguishes it from adjacent bodies of rock, and which occupies a particular position in the layers of rock exp ...

with outcrops all around the Dead Sea Basin: in the

Negev Desert The Negev ( ; ) or Naqab (), is a desert and semidesert region of southern Israel. The region's largest city and administrative capital is Beersheba (pop. ), in the north. At its southern end is the Gulf of Aqaba and the resort town, resort city ...

Israel Israel, officially the State of Israel, is a country in West Asia. It Borders of Israel, shares borders with Lebanon to the north, Syria to the north-east, Jordan to the east, Egypt to the south-west, and the Mediterranean Sea to the west. Isr ...

, in the

Judaean Desert The Judaean Desert or Judean Desert (, ) is a desert in the West Bank and Israel that stretches east of the ridge of the Judaean Mountains and in their rain shadow, so east of Jerusalem, and descends to the Dead Sea. Under the name El-Bariyah, ...

on the

West Bank The West Bank is located on the western bank of the Jordan River and is the larger of the two Palestinian territories (the other being the Gaza Strip) that make up the State of Palestine. A landlocked territory near the coast of the Mediter ...

, and in western

Jordan Jordan, officially the Hashemite Kingdom of Jordan, is a country in the Southern Levant region of West Asia. Jordan is bordered by Syria to the north, Iraq to the east, Saudi Arabia to the south, and Israel and the occupied Palestinian ter ...

. It includes late

Cretaceous The Cretaceous ( ) is a geological period that lasted from about 143.1 to 66 mya (unit), million years ago (Mya). It is the third and final period of the Mesozoic Era (geology), Era, as well as the longest. At around 77.1 million years, it is the ...

Eocene The Eocene ( ) is a geological epoch (geology), epoch that lasted from about 56 to 33.9 million years ago (Ma). It is the second epoch of the Paleogene Period (geology), Period in the modern Cenozoic Era (geology), Era. The name ''Eocene'' comes ...

aged impure

limestone Limestone is a type of carbonate rock, carbonate sedimentary rock which is the main source of the material Lime (material), lime. It is composed mostly of the minerals calcite and aragonite, which are different Polymorphism (materials science) ...

along with

coal Coal is a combustible black or brownish-black sedimentary rock, formed as rock strata called coal seams. Coal is mostly carbon with variable amounts of other Chemical element, elements, chiefly hydrogen, sulfur, oxygen, and nitrogen. Coal i ...

bearing

chalk Chalk is a soft, white, porous, sedimentary carbonate rock. It is a form of limestone composed of the mineral calcite and originally formed deep under the sea by the compression of microscopic plankton that had settled to the sea floor. Ch ...

and

marl Marl is an earthy material rich in carbonate minerals, Clay minerals, clays, and silt. When Lithification, hardened into rock, this becomes marlstone. It is formed in marine or freshwater environments, often through the activities of algae. M ...

. The rocks have been subjected to pyrometamorphism resulting from combustion of contained or underlying coal or

hydrocarbon In organic chemistry, a hydrocarbon is an organic compound consisting entirely of hydrogen and carbon. Hydrocarbons are examples of group 14 hydrides. Hydrocarbons are generally colourless and Hydrophobe, hydrophobic; their odor is usually fain ...

deposits. The formation is named for exposures in the Hatrurim Basin which lies west of the

Dead Sea The Dead Sea (; or ; ), also known by #Names, other names, is a landlocked salt lake bordered by Jordan to the east, the Israeli-occupied West Bank to the west and Israel to the southwest. It lies in the endorheic basin of the Jordan Rift Valle ...

.Mindat location
/ref> During the 1960s, a group of scientists from the

Hebrew University of Jerusalem The Hebrew University of Jerusalem (HUJI; ) is an Israeli public university, public research university based in Jerusalem. Co-founded by Albert Einstein and Chaim Weizmann in July 1918, the public university officially opened on 1 April 1925. ...

, including Yaakov Ben-Tor, and Lisa Heller-Kallai, discovered that the Hatrurim Formation contained several rare, if not unique, mineral assemblages. The formation is the type locality for five unusual minerals and noted for other minerals serving as reference for mineral phases formed at high temperature in the clinker of

Portland cement Portland cement is the most common type of cement in general use around the world as a basic ingredient of concrete, mortar (masonry), mortar, stucco, and non-specialty grout. It was developed from other types of hydraulic lime in England in th ...

Shulamit Gross Shulamit Gross (; lived 1 October 1923 – 19 Sep 2012) was an Israeli mineralogist and geologist who studied the Hatrurim Formation. Biography Gross was born as Shulamit Lifszyc in Grodno, Poland (today, Hrodna, Belarus). She was the daughte ...

, an Israeli geologist and mineralogist, continued to study these rare minerals. In 1977, she published a monograph describing 123 mineral species discovered in the Hatrurim Formation. Five were previously known only from a single locality, and eight others were known only as artificial products of the cement industry. Gross also discovered several minerals completely new to science: bentorite, ye'elimite, and hatrurite. A fourth mineral discovered by Gross was only described later by Dietmar Weber and Adolf Bischoff, which they named

grossite Grossite is a calcium aluminium oxide mineral with formula CaAl4O7. It is a colorless to white vitreous mineral which crystallizes in the monoclinic crystal system. Grossite was first described 1994 for an occurrence in the Hatrurim Formation of ...

after Shulamit. Gross demonstrated that the unique mineral assemblages discovered in the Hatrurim Formation were formed by pyrometamorphism, and she managed to recreate in the laboratory most of the minerals by heating the precursor sedimentary rocks of the Ghareb and Taqiye formations. In 2011, a new

perovskite Perovskite (pronunciation: ) is a calcium titanium oxide mineral composed of calcium titanate (chemical formula ). Its name is also applied to the class of compounds which have the same type of crystal structure as , known as the perovskite (stru ...

-related mineral from the Hatrurim Basin was named shulamitite to honor Shulamit Gross for her works. Shulamitite, ideally , is a mineral intermediate between

() and

brownmillerite Brownmillerite is a rare oxide mineral with chemical formula . It is named for Lorrin Thomas Brownmiller (1902–1990), chief chemist of the Alpha Portland Cement Company, Easton, Pennsylvania. Discovery and occurrence The chemical compound was ...

(), a mineral of the cement clinker.

References

Geologic formations of Israel Geologic formations of Jordan Dead Sea basin {{Asia-geologic-formation-stub