Sepiolite, also known in
English
English usually refers to:
* English language
* English people
English may also refer to:
Peoples, culture, and language
* ''English'', an adjective for something of, from, or related to England
** English national id ...
by the
German
German(s) may refer to:
* Germany (of or related to)
**Germania (historical use)
* Germans, citizens of Germany, people of German ancestry, or native speakers of the German language
** For citizens of Germany, see also German nationality law
**Ger ...
name meerschaum ( , ; ; meaning "
sea foam
Sea foam, ocean foam, beach foam, or spume is a type of foam created by the agitation of seawater, particularly when it contains higher concentrations of dissolved organic matter (including proteins, lignins, and lipids) derived from sources s ...
"), is a soft white
clay mineral
Clay minerals are hydrous aluminium phyllosilicates (e.g. kaolin, Al2 Si2 O5( OH)4), sometimes with variable amounts of iron, magnesium, alkali metals, alkaline earths, and other cations found on or near some planetary surfaces.
Clay mineral ...
, often used to make
tobacco pipe
A tobacco pipe, often called simply a pipe, is a device specifically made to smoke tobacco. It comprises a chamber (the bowl) for the tobacco from which a thin hollow stem (shank) emerges, ending in a mouthpiece. Pipes can range from very sim ...
s (known as
meerschaum pipe
A meerschaum pipe is a smoking pipe made from the mineral sepiolite, also known as meerschaum. Meerschaum (, German for "sea foam") is sometimes found floating on the Black Sea and is rather suggestive of sea foam (hence the German origin of ...
s). A complex
magnesium
Magnesium is a chemical element with the symbol Mg and atomic number 12. It is a shiny gray metal having a low density, low melting point and high chemical reactivity. Like the other alkaline earth metals (group 2 of the periodic ...
silicate, a typical
chemical formula
In chemistry, a chemical formula is a way of presenting information about the chemical proportions of atoms that constitute a particular chemical compound or molecule, using chemical element symbols, numbers, and sometimes also other symbols, ...
for which is Mg
4Si
6O
15(OH)
2·6H
2O, it can be present in fibrous, fine-particulate, and solid forms.
The fibrous clay minerals have recently been shown to exist as a continuous polysomatic series where the endmembers are sepiolite and palygorskite. There is a continuous variation in chemical composition from sepiolite, the most magnesic and trioctahedral endmember, to palygorskite, the least magnesic, most Al- Fe- bearing, dioctahedral endmember.
Originally named ''meerschaum'' by
Abraham Gottlob Werner
Abraham Gottlob Werner (; 25 September 174930 June 1817) was a German geologist who set out an early theory about the stratification of the Earth's crust and propounded a history of the Earth that came to be known as Neptunism. While most ten ...
in 1788, it was named ''sepiolite'' by
Ernst Friedrich Glocker
Ernst Friedrich Glocker (1 May 1793 – 18 July 1858) was a German mineralogist, geologist and paleontologist. Biography
From 1810 he studied theology, philosophy and sciences at the University of Tübingen, and afterwards continued his educatio ...
in 1847 for an occurrence in
Bettolino,
Baldissero Canavese
Baldissero Canavese is a ''comune'' (municipality) in the Metropolitan City of Turin in the Italian region Piedmont, about north of Turin.
Baldissero Canavese borders the following municipalities: Castellamonte, Vistrorio, Vidracco, Strambine ...
,
Torino Province
The former Province of Turin ( it, Provincia di Torino; pms, Provinsa ëd Turin; french: Province de Turin) was a province in the Piedmont region of Italy. Its capital was the city of Turin. The province existed until 31 December 2014, when it wa ...
,
Piedmont
it, Piemontese
, population_note =
, population_blank1_title =
, population_blank1 =
, demographics_type1 =
, demographics1_footnotes =
, demographics1_title1 =
, demographics1_info1 =
, demographics1_title2 ...
,
Italy
Italy ( it, Italia ), officially the Italian Republic, ) or the Republic of Italy, is a country in Southern Europe. It is located in the middle of the Mediterranean Sea, and its territory largely coincides with the homonymous geographical ...
. The name comes from
Greek
Greek may refer to:
Greece
Anything of, from, or related to Greece, a country in Southern Europe:
*Greeks, an ethnic group.
*Greek language, a branch of the Indo-European language family.
**Proto-Greek language, the assumed last common ancestor ...
''sepion'' (σήπιον), meaning "
cuttlebone
Cuttlebone, also known as cuttlefish bone, is a hard, brittle internal structure (an internal shell) found in all members of the family Sepiidae, commonly known as cuttlefish, within the cephalopods. In other cephalopod families it is calle ...
" (the porous internal shell of the
cuttlefish
Cuttlefish or cuttles are marine molluscs of the order Sepiida. They belong to the class Cephalopoda which also includes squid, octopuses, and nautiluses. Cuttlefish have a unique internal shell, the cuttlebone, which is used for control ...
), + ''lithos'' (λίθος), meaning ''stone'', after a perceived resemblance of this mineral to cuttlebone.
[ Because of its low ]relative density
Relative density, or specific gravity, is the ratio of the density (mass of a unit volume) of a substance to the density of a given reference material. Specific gravity for liquids is nearly always measured with respect to water at its densest ...
and its high porosity, it may float upon water, hence its German name. It is sometimes found floating on the Black Sea
The Black Sea is a marginal mediterranean sea of the Atlantic Ocean lying between Europe and Asia, east of the Balkans, south of the East European Plain, west of the Caucasus, and north of Anatolia. It is bounded by Bulgaria, Georgia, ...
and rather suggestive of sea-foam, hence the German origin of the name as well as the French name for the same substance, ''écume de mer''.[
]
Characteristics
Sepiolite is opaque and off-white, grey or cream colour, breaking with a conchoidal or fine earthy fracture, and occasionally fibrous in texture.[ Due to the fact it can be readily scratched with the finger nail, its ]hardness
In materials science, hardness (antonym: softness) is a measure of the resistance to localized plastic deformation induced by either mechanical indentation or abrasion (mechanical), abrasion. In general, different materials differ in their hardn ...
is ranked at about 2 on the Mohs scale
The Mohs scale of mineral hardness () is a qualitative ordinal scale, from 1 to 10, characterizing scratch resistance of various minerals through the ability of harder material to scratch softer material.
The scale was introduced in 1812 by the ...
.[ The ]specific gravity
Relative density, or specific gravity, is the ratio of the density (mass of a unit volume) of a substance to the density of a given reference material. Specific gravity for liquids is nearly always measured with respect to water (molecule), wa ...
varies from 0.988 to 1.279, but the porosity of the mineral may lead to error. Sepiolite is a hydrous magnesium silicate
Talc, or talcum, is a clay mineral, composed of hydrated magnesium silicate with the chemical formula Mg3Si4O10(OH)2. Talc in powdered form, often combined with corn starch, is used as baby powder. This mineral is used as a thickening agent ...
[ having the chemical formula Mg4Si6O15(OH)2·6H2O.
Sepiolite can be identified in hand specimen by applying a drop of a saturated solution of ]methyl orange
Methyl orange is a pH indicator frequently used in titration because of its clear and distinct color variance at different pH values. Methyl orange shows red color in acidic medium and yellow color in basic medium. Because it changes color at the ...
on the sample. A positive test result for sepiolite turns purple. This can distinguish calcite from sepiolite in the field: sepiolite reacts to change the methyl orange to a shade of purple where calcite remains orange.
When first extracted, sepiolite is soft. However, it hardens on exposure to sun heat or when dried in a warm room.[ Sepiolite can be distinguished from silica or calcite-cemented material by slaking: calcite-cemented material slakes in acid, and silica-cemented material slakes in alkali or alternating acid/alkali.] Sepiolite-cemented material has been termed "sepiocrete" as calcrete, silcrete or ferricrete is used to refer to materials cemented by calcite, silica or iron . Soils that contain significant quantities of sepiolite may be more appropriately termed "sepiolitic" or "petrosepiolitic" depending on the degree of cementation.
Stabilization of nanosepiolite suspensions was improved using mechanical dispersion and bio-based and synthetic polyelectrolytes. Surface energy and nanoroughness were studied in two sepiolite samples.
Location
Most of the sepiolite of commerce is obtained chiefly from the plain of Eskişehir
Eskişehir ( , ; from "old" and "city") is a city in northwestern Turkey and the capital of the Eskişehir Province. The urban population of the city is 898,369 with a metropolitan population of 797,708. The city is located on the banks of the ...
in Turkey
Turkey ( tr, Türkiye ), officially the Republic of Türkiye ( tr, Türkiye Cumhuriyeti, links=no ), is a list of transcontinental countries, transcontinental country located mainly on the Anatolia, Anatolian Peninsula in Western Asia, with ...
, between Istanbul
Istanbul ( , ; tr, İstanbul ), formerly known as Constantinople ( grc-gre, Κωνσταντινούπολις; la, Constantinopolis), is the List of largest cities and towns in Turkey, largest city in Turkey, serving as the country's economic, ...
and Ankara
Ankara ( , ; ), historically known as Ancyra and Angora, is the capital of Turkey. Located in the central part of Anatolia, the city has a population of 5.1 million in its urban center and over 5.7 million in Ankara Province, mak ...
. It occurs there in irregular nodular masses, in alluvial deposits, which are extensively worked for its extraction. It is said that in this district, there are 4000 shafts leading to horizontal galleries for extraction of the sepiolite.[ The principal workings are at Sepetçi Ocağı and Kemikçi Ocağı, about 20 miles southeast of ]Eskişehir
Eskişehir ( , ; from "old" and "city") is a city in northwestern Turkey and the capital of the Eskişehir Province. The urban population of the city is 898,369 with a metropolitan population of 797,708. The city is located on the banks of the ...
.[ The mineral is associated with ]magnesite
Magnesite is a mineral with the chemical formula ( magnesium carbonate). Iron, manganese, cobalt, and nickel may occur as admixtures, but only in small amounts.
Occurrence
Magnesite occurs as veins in and an alteration product of ultramafic ...
(magnesium carbonate
Magnesium carbonate, (archaic name magnesia alba), is an inorganic salt that is a colourless or white solid. Several hydrated and basic forms of magnesium carbonate also exist as minerals.
Forms
The most common magnesium carbonate forms are ...
), the primitive source of both minerals being a serpentine
Serpentine may refer to:
Shapes
* Serpentine shape, a shape resembling a serpent
* Serpentine curve, a mathematical curve
* Serpentine, a type of riding figure
Science and nature
* Serpentine subgroup, a group of minerals
* Serpentinite, a ...
.[
Sepiolite is also found, though less abundantly, in ]Greece
Greece,, or , romanized: ', officially the Hellenic Republic, is a country in Southeast Europe. It is situated on the southern tip of the Balkans, and is located at the crossroads of Europe, Asia, and Africa. Greece shares land borders wit ...
, as at Thebes, and in the islands of Euboea
Evia (, ; el, Εύβοια ; grc, Εὔβοια ) or Euboia (, ) is the second-largest Greek island in area and population, after Crete. It is separated from Boeotia in mainland Greece by the narrow Euripus Strait (only at its narrowest ...
and Samos
Samos (, also ; el, Σάμος ) is a Greek island in the eastern Aegean Sea, south of Chios, north of Patmos and the Dodecanese, and off the coast of western Turkey, from which it is separated by the -wide Mycale Strait. It is also a sepa ...
.[ It occurs also in ]serpentine
Serpentine may refer to:
Shapes
* Serpentine shape, a shape resembling a serpent
* Serpentine curve, a mathematical curve
* Serpentine, a type of riding figure
Science and nature
* Serpentine subgroup, a group of minerals
* Serpentinite, a ...
at Hrubschitz near Kromau in Moravia
Moravia ( , also , ; cs, Morava ; german: link=yes, Mähren ; pl, Morawy ; szl, Morawa; la, Moravia) is a historical region in the east of the Czech Republic and one of three historical Czech lands, with Bohemia and Czech Silesia.
Th ...
. Additionally, sepiolite is found to a limited extent at certain localities in France
France (), officially the French Republic ( ), is a country primarily located in Western Europe. It also comprises of overseas regions and territories in the Americas and the Atlantic, Pacific and Indian Oceans. Its metropolitan ar ...
and Spain
, image_flag = Bandera de España.svg
, image_coat = Escudo de España (mazonado).svg
, national_motto = '' Plus ultra'' ( Latin)(English: "Further Beyond")
, national_anthem = (English: "Royal March")
, ...
, and is known in Morocco
Morocco (),, ) officially the Kingdom of Morocco, is the westernmost country in the Maghreb region of North Africa. It overlooks the Mediterranean Sea to the north and the Atlantic Ocean to the west, and has land borders with Algeria ...
.[ In the ]United States
The United States of America (U.S.A. or USA), commonly known as the United States (U.S. or US) or America, is a country primarily located in North America. It consists of 50 U.S. state, states, a Washington, D.C., federal district, five ma ...
, it occurs in serpentine in Pennsylvania
Pennsylvania (; (Pennsylvania Dutch: )), officially the Commonwealth of Pennsylvania, is a state spanning the Mid-Atlantic, Northeastern, Appalachian, and Great Lakes regions of the United States. It borders Delaware to its southeast, Ma ...
(as at Nottingham, Chester County) and in South Carolina
)'' Animis opibusque parati'' ( for, , Latin, Prepared in mind and resources, links=no)
, anthem = "Carolina";" South Carolina On My Mind"
, Former = Province of South Carolina
, seat = Columbia
, LargestCity = Charleston
, LargestMetro = G ...
and Utah
Utah ( , ) is a state in the Mountain West subregion of the Western United States. Utah is a landlocked U.S. state bordered to its east by Colorado, to its northeast by Wyoming, to its north by Idaho, to its south by Arizona, and to its ...
.[ In ]Somalia
Somalia, , Osmanya script: 𐒈𐒝𐒑𐒛𐒐𐒘𐒕𐒖; ar, الصومال, aṣ-Ṣūmāl officially the Federal Republic of SomaliaThe ''Federal Republic of Somalia'' is the country's name per Article 1 of thProvisional Constitut ...
it is mined in the El Buur El Buur (; so, Ceelbuur) is a town located in the state of Galmudug in central Somalia. It was formerly the capital of the Galgaduud region.
Residents
El Buur has been inhabited since at least the 13th century. During the Ajuran Sultanate it s ...
district.
Sepiolite occurs as a secondary mineral associated with serpentine
Serpentine may refer to:
Shapes
* Serpentine shape, a shape resembling a serpent
* Serpentine curve, a mathematical curve
* Serpentine, a type of riding figure
Science and nature
* Serpentine subgroup, a group of minerals
* Serpentinite, a ...
. It can occur as a precipitate in arid environments. It may be associated with dolomite Dolomite may refer to:
*Dolomite (mineral), a carbonate mineral
*Dolomite (rock), also known as dolostone, a sedimentary carbonate rock
*Dolomite, Alabama, United States, an unincorporated community
*Dolomite, California, United States, an unincor ...
and opal
Opal is a hydrated amorphous form of silica (SiO2·''n''H2O); its water content may range from 3 to 21% by weight, but is usually between 6 and 10%. Due to its amorphous property, it is classified as a mineraloid, unlike crystalline forms ...
.[
Owing to its fibrous mineral nature, sepiolite veins may contain the hazardous material asbestos; however, this is true of only a very rare form of sepiolite, as the two are formed in very different environments.] Even where asbestos is not present, sepiolite is often mistaken for it. Careful analytical techniques such as X-ray diffraction (XRD) are able to easily distinguish the two.
Carved Turkish meerschaum products traditionally were made in manufacturing centers such as Vienna
en, Viennese
, iso_code = AT-9
, registration_plate = W
, postal_code_type = Postal code
, postal_code =
, timezone = CET
, utc_offset = +1
, timezone_DST ...
. Since the 1970s, though, Turkey
Turkey ( tr, Türkiye ), officially the Republic of Türkiye ( tr, Türkiye Cumhuriyeti, links=no ), is a list of transcontinental countries, transcontinental country located mainly on the Anatolia, Anatolian Peninsula in Western Asia, with ...
has banned the exportation of meerschaum nodules, trying to set up a local meerschaum industry. The once famous manufacturers have therefore disappeared and European pipe producers turned to other sources for their pipes.
In the African Great Lakes
The African Great Lakes ( sw, Maziwa Makuu; rw, Ibiyaga bigari) are a series of lakes constituting the part of the Rift Valley lakes in and around the East African Rift. They include Lake Victoria, the second-largest fresh water lake in the ...
region, large deposits of meerschaum were found in Tanganyika
Tanganyika may refer to:
Places
* Tanganyika Territory (1916–1961), a former British territory which preceded the sovereign state
* Tanganyika (1961–1964), a sovereign state, comprising the mainland part of present-day Tanzania
* Tanzania M ...
. The main deposit comes from the Amboseli
Amboseli National Park, formerly Maasai Amboseli Game Reserve, is a national park in Kajiado South Constituency in Kajiado County, Kenya. The park is in size at the core of an ecosystem that spreads across the Kenya-Tanzania border. The local ...
basin surrounding the Lake Amboseli. Tanganyika Meerschaum is normally stained in shades of brown, black and yellow, and is considered to be somewhat inferior to Meerschaum from Turkey. The raw material was primarily mined by the Tanganyika Meerschaum Corporation and uncounted pipemakers throughout the world were supplied with Amboseli Meerschaum.
Significant quantities of sepiolite occur in soils of the arid west of South Africa. There is a geographic variation from the sepiolite-containing soils at the coast to palygorskite-containing soils inland that mirrors the sepiolite-palygorskite compositional continuum from sepiolite, the most magnesic and trioctahedral endmember at the coast, to palygorskite, the least magnesic endmember farthest inland. There are many instances of cemented sepiolite layers. The positive environment effect in the arid region is that sepiolite increases plant available water in the sandy soils. A negative effect is that the cemented sepiolite causes considerable geotechnical and geometallurgical difficulty for extracting the heavy minerals from the sepiolite-rich sands.
Applications
Carved pipes
Meerschaum has occasionally been used as a substitute for soapstone
Soapstone (also known as steatite or soaprock) is a talc-schist, which is a type of metamorphic rock. It is composed largely of the magnesium rich mineral talc. It is produced by dynamothermal metamorphism and metasomatism, which occur in the ...
, fuller's earth
Fuller's earth is any clay material that has the capability to decolorize oil or other liquids without the use of harsh chemical treatment. Fuller's earth typically consists of palygorskite ( attapulgite) or bentonite.
Modern uses of fuller's e ...
, and as a building material; but its chief use is for smoking pipe
A smoking pipe is used to inhale the smoke of a burning substance; most common is a tobacco pipe, which can also accommodate almost any other substance. Pipes are commonly made from briar, heather, corn, meerschaum, clay, cherry, glass, porcela ...
s and cigarette holder
A cigarette holder is a fashion accessory, a slender tube in which a cigarette is held for smoking. Most frequently made of silver, jade or bakelite (popular in the past but now wholly replaced by modern plastics), cigarette holders were con ...
s.[ The first recorded use of meerschaum for making pipes was around 1723 and quickly became prized as the perfect material for providing a cool, dry, flavorful smoke. The ]porous
Porosity or void fraction is a measure of the void (i.e. "empty") spaces in a material, and is a fraction of the volume of voids over the total volume, between 0 and 1, or as a percentage between 0% and 100%. Strictly speaking, some tests measure ...
nature of meerschaum draws moisture and tobacco tar into the stone. Meerschaum became a premium substitute for the clay pipes of the day and remains prized to this day, though since the mid-1800s briar pipes have become the most common pipes for smoking
Smoking is a practice in which a substance is burned and the resulting smoke is typically breathed in to be tasted and absorbed into the bloodstream. Most commonly, the substance used is the dried leaves of the tobacco plant, which have bee ...
.
When smoked, meerschaum pipes gradually change color, and old meerschaums will turn incremental shades of yellow, orange, red, and amber from the base on up. When prepared for use as a pipe, the natural nodules
Nodule may refer to:
*Nodule (geology), a small rock or mineral cluster
*Manganese nodule, a metallic concretion found on the seafloor
*Nodule (medicine), a small aggregation of cells
*Root nodule
Root nodules are found on the roots of plants, p ...
are first scraped to remove the red earthy matrix, then dried, again scraped and polished with wax.[ The crudely shaped masses thus prepared are turned and ]carved
Carving is the act of using tools to shape something from a material by scraping away portions of that material. The technique can be applied to any material that is solid enough to hold a form even when pieces have been removed from it, and ...
, smoothed with glass-paper
upright=1.35, Sheets of sandpaper with different grit sizes (40 (coarse), 80, 150, 240, 600 (fine)).
Sandpaper and glasspaper are names used for a type of coated abrasive that consists of sheets of paper or cloth with abrasive material glued to ...
, heated in wax or stearine
Stearin , or tristearin, or glyceryl tristearate is an odourless, white powder. It is a triglyceride derived from three units of stearic acid. Most triglycerides are derived from at least two and more commonly three different fatty acids. Like o ...
, and finally polished with bone ash
Bone ash is a white material produced by the calcination of bones. Typical bone ash consists of about 55.82% calcium oxide, 42.39% phosphorus pentoxide, and 1.79% water. The exact composition of these compounds varies depending upon the type of bo ...
, etc.[
]
Other uses and substitutes
Sepiolite is renowned industrially for its water-holding and sorptive capacities. It is a common ingredient in cat litter and in agricultural applications such as seed coatings. Sepiolite increases plant available water in sandy soil.
In Somalia
Somalia, , Osmanya script: 𐒈𐒝𐒑𐒛𐒐𐒘𐒕𐒖; ar, الصومال, aṣ-Ṣūmāl officially the Federal Republic of SomaliaThe ''Federal Republic of Somalia'' is the country's name per Article 1 of thProvisional Constitut ...
and Djibouti
Djibouti, ar, جيبوتي ', french: link=no, Djibouti, so, Jabuuti officially the Republic of Djibouti, is a country in the Horn of Africa, bordered by Somalia to the south, Ethiopia to the southwest, Eritrea in the north, and the Re ...
, sepiolite is used to make the dabqaad
The dabqaad (Somali for "fire raiser"), also known as unsi or girgire, is an incense burner, or censer. With either one or two handles, it is commonly used in Somalia, Ethiopia and Djibouti.
Usage and production
Dabqaads are traditionally used t ...
, a traditional incense
Incense is aromatic biotic material that releases fragrant smoke when burnt. The term is used for either the material or the aroma. Incense is used for aesthetic reasons, religious worship, aromatherapy, meditation, and ceremony. It may also ...
burner. The mineral is mined in the town of El Buur El Buur (; so, Ceelbuur) is a town located in the state of Galmudug in central Somalia. It was formerly the capital of the Galgaduud region.
Residents
El Buur has been inhabited since at least the 13th century. During the Ajuran Sultanate it s ...
, the latter of which serves as a center for quarrying
A quarry is a type of open-pit mine in which dimension stone, rock, construction aggregate, riprap, sand, gravel, or slate is excavated from the ground. The operation of quarries is regulated in some jurisdictions to reduce their e ...
. El Buur is also the place of origin of the local pipe-making industry.
Imitations are made in plaster of Paris
Plaster is a building material used for the protective or decorative coating of walls and ceilings and for moulding and casting decorative elements. In English, "plaster" usually means a material used for the interiors of buildings, while "r ...
treated with paraffin and dyed with two types of coloured tree resins; Gamborge and Dragon's blood. Other methods of imitation are said to employ potatoes in the process.
The soft, white, earthy mineral from Långbanshyttan, in Värmland
Värmland () also known as Wermeland, is a ''landskap'' (historical province) in west-central Sweden. It borders Västergötland, Dalsland, Dalarna, Västmanland, and Närke, and is bounded by Norway in the west. Latin name versions are ...
, Sweden, known as aphrodite
Aphrodite ( ; grc-gre, Ἀφροδίτη, Aphrodítē; , , ) is an ancient Greek religion, ancient Greek goddess associated with love, lust, beauty, pleasure, passion (emotion), passion, and procreation. She was syncretized with the Roman god ...
( el, sea foam), is closely related to sepiolite.[
In construction, sepiolite can be used in ]lime mortar
Lime mortar or torching is composed of lime and an aggregate such as sand, mixed with water. The ancient Egyptians were the first to use lime mortars, which they used to plaster their temples. In addition, the Egyptians also incorporated various ...
s as water reservoir.
Processes for bacterial transformation based on the Yoshida Effect can utilize sepiolite as an acicular nanofiber
Nanofibers are fibers with diameters in the nanometer range (typically, between 1 nm and 1 μm). Nanofibers can be generated from different polymers and hence have different physical properties and application potentials. Examples of natural polyme ...
. The Yoshida effect is the transfer of DNA to a bacterial cell using a mineral fibre that is a few billionths of a meter thick, essentially using the fibre as a tool to physically transfer the genetic material.
See also
*
*
*
* List of Minerals
This is a list of minerals for which there are articles on Wikipedia.
Minerals are distinguished by various chemical and physical properties. Differences in chemical composition and crystal structure distinguish the various ''species''. Within a m ...
References
External links
IMA Europe - Sepiolite factsheet
{{Authority control
Clay minerals group
Magnesium minerals
Orthorhombic minerals
Minerals in space group 52
Phyllosilicates
Luminescent minerals
Pipe smoking