Pelagosite is a form of pisolitic aragonite ( Ca C O₃) whose type locality is the

Croatia , image_flag = Flag of Croatia.svg , image_coat = Coat of arms of Croatia.svg , anthem = " Lijepa naša domovino"("Our Beautiful Homeland") , image_map = , map_caption = , capi ...

n island group of

Palagruža Palagruža (; it, Pelagosa) is a small Croatian archipelago in the middle of the Adriatic Sea. It is uninhabited, except by lighthouse staff and occasional summer tourists. Geography It consists of one larger island, called ''Vela'' or ''Vel ...

(Italian ''Pelagosa'', whence the name) in the middle of the

Adriatic The Adriatic Sea () is a body of water separating the Italian Peninsula from the Balkan Peninsula. The Adriatic is the northernmost arm of the Mediterranean Sea, extending from the Strait of Otranto (where it connects to the Ionian Sea) to the ...

. It was identified by R. Moser in ''Mineralogische und petrographische Mitteilungen'', new series (Vienna) 1 (1878), 174. It has a higher content of

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 ...

, strontium carbonate,

calcium sulfate Calcium sulfate (or calcium sulphate) is the inorganic compound with the formula CaSO4 and related hydrates. In the form of γ-anhydrite (the anhydrous form), it is used as a desiccant. One particular hydrate is better known as plaster of Paris ...

(

gypsum Gypsum is a soft sulfate mineral composed of calcium sulfate dihydrate, with the chemical formula . It is widely mined and is used as a fertilizer and as the main constituent in many forms of plaster, blackboard or sidewalk chalk, and drywa ...

) and

silicon dioxide Silicon dioxide, also known as silica, is an oxide of silicon with the chemical formula , most commonly found in nature as quartz and in various living organisms. In many parts of the world, silica is the major constituent of sand. Silica is one ...

(

silica Silicon dioxide, also known as silica, is an oxide of silicon with the chemical formula , most commonly found in nature as quartz and in various living organisms. In many parts of the world, silica is the major constituent of sand. Silica is ...

) than is found in typical limy

sediment Sediment is a naturally occurring material that is broken down by processes of weathering and erosion, and is subsequently transported by the action of wind, water, or ice or by the force of gravity acting on the particles. For example, sand ...

s elsewhere. It occurs as a superficial

calcareous Calcareous () is an adjective meaning "mostly or partly composed of calcium carbonate", in other words, containing lime or being chalky. The term is used in a wide variety of scientific disciplines. In zoology ''Calcareous'' is used as an ad ...

crust no more than a few millimetres thick, which is generally white, grey, or brownish with a pearly lustre. It was believed to be formed in the

intertidal zone The intertidal zone, also known as the foreshore, is the area above water level at low tide and underwater at high tide (in other words, the area within the tidal range). This area can include several types of habitats with various species ...

by saltwater spray and

evaporation Evaporation is a type of vaporization that occurs on the surface of a liquid as it changes into the gas phase. High concentration of the evaporating substance in the surrounding gas significantly slows down evaporation, such as when h ...

, but an

alga Algae (; singular alga ) is an informal term for a large and diverse group of photosynthetic eukaryotic organisms. It is a polyphyletic grouping that includes species from multiple distinct clades. Included organisms range from unicellular mic ...

l contribution has recently been suggested (Montanari and others (2007)), following an overlooked earlier proposal by E. Onorato in 1926.

References

Montanari, A., et al. (2007) ''Rediscovering pelagosite,'' Geophysical Research Abstracts, 9

External links

* Calcium minerals Carbonate minerals Limestone {{carbonate-mineral-stub