EVER since Claringbull and Hey 0952) first described the mineral sinhalite, which had previously been identified as gem peridot, other discoveries have been reported (Meixner, I953; Zwaan, I955; Payne, ~958; Giibelin, 1962). Essentially sinhalite is found in skarn assemblages from contact zones of metamorphosed carbonate rocks with, for example, Archean gneiss (Aldan massif, U.S.S.R., Shabynin,...

Coccolithophores are an abundant phytoplankton group that exhibit remarkable diversity in their biology, ecology and calcitic exoskeletons (coccospheres). Their extensive fossil record is a testament to their important biogeochemical role and is a valuable archive of biotic responses to environmental change stretching back over 200 million years. However, to realise the full potential of this a...

Shell microstructures in some of the oldest known mollusk fossils (from the early to middle Cambrian Period; 542 to 510 million years ago) are diverse, strong, and in some cases unusual. We herein review our recent work focused on different aspects of shell microstructures in Cambrian mollusks, briefly summarizing some of the major conclusions from a few of our recent publications and adding so...

Aminostratigraphies of Quaternary non-marine deposits in Europe have been previously based on the racemization of a single amino acid in aragonitic shells from land and freshwater molluscs. The value of analysing multiple amino acids from the opercula of the freshwater gastropod Bithynia, which are composed of calcite, has been demonstrated. The protocol used for the isolation of intra-crystall...

The boundary between the African and Arabian plates in the Southern Red Sea region is displaced inland in the northern Afar rift, where it is marked by the Red Sea-parallel Erta Ale, Alaita, and Tat Ali volcanic ridges. The Erta Ale is offset by about 20 and 40 km from the two en echelon ridges to the south. The offset area is highly seismic and marked by a depression filled by lake Afrera, a s...

Empty mollusk shells may act as colonization surfaces for sclerobionts depending on the physical, chemical, and biological attributes of the shells. However, the main factors that can affect the establishment of an organism on hard substrates and the colonization patterns on modern and time-averaged shells remain unclear. Using experimental and field approaches, we compared sclerobiont (i.e., b...

In the field of microbial biomineralization, much of the scientific attention is focused on processes carried out by prokaryotes, in particular bacteria, even though fungi are also known to be involved in biogeochemical cycles in numerous ways. They are traditionally recognized as key players in organic matter recycling, as nutrient suppliers via mineral weathering, as well as large producers o...

Biologically controlled mineralization features an orchestrated balance among various controlling factors such as spatial delineation, template promotion, crystal growth modification and cessation, and so on. Highly ordered calcium carbonate lamellae formed in the nacreous layers of mollusk (aragonite), the foliated calcitic layers of mollusk (calcite), or the semi-nacre of brachiopods (calcite...

Understanding the vulnerability of marine calcifiers to ocean acidification is a critical issue, especially in Southern Ocean (SO), which likely be one first, and most severely affected regions. Since industrial revolution, ~30% anthropogenic CO 2 has been absorbed by global oceans. Average surface seawater pH levels have already decreased 0.1 are projected decline ~0.3 year 2100. This process,...

Calcium carbonate hexahydrate (ikaite) is a rare mineral that forms as metastable species in the organic-carbon-rich sediments of King George Basin, Bransfield Strait, Antarctica, consequence early diagenetic decomposition organic matter under cold water (−1.4 °C) and high pressure (200 bar) conditions. Large crystals grow sediment immediately below transition between microbial sulfate reductio...