<p>Acantharians are planktonic protists (abundant in today oceans), sister-group to polycystine Radiolarians, that have the particularity of biomineralizing complex skeletons in strontium sulfate SrSO<sub>4</sub> (i. e. celestine). 
Those protists have no (as far as I know) fossil record for the good reason that celestine is soluble in seawater once the organism decayed. 
However it has been speculated (e. g. <strong>Bernstein et al. 1992</strong>) that acantharian-derived celestine could be at the origin of the formation of Sr-rich barite.  </p>

<p>What is the status of this hypothesis? If this is still considered true, is there a way to differentiate unambiguously acantharian-derived barite from other kind of barite?</p>

<p>This would of course have interesting paleontological implications.</p>

<p><sub>Source:<br>
Bernstein, R. E., Byrne, R. H., Betzer, P. R., Greco, A. M., 1992. <a href="http://www.sciencedirect.com/science/article/pii/0016703792903042" rel="nofollow">Morphologies and transformations of celestite in seawater: The role of acantharians in strontium and barium geochemistry</a>. Geochimica et Cosmochimica Acta, 56: 3273-3279.
</sub></p>

CC BY-SA 3.0
2014-10-11T09:20:09.950Z
The correct mineral name would be celestine, not celestite. It is the official name recognised by the IMA.
Gimelist
<paleontology><diagenesis><sedimentology><biomineralization>
Barite and Acantharians
plannapus
# Barite and Acantharians

(Asked by: username_0 on 2014-04-22)

Acantharians are planktonic protists (abundant in today oceans), sister-group to polycystine Radiolarians, that have the particularity of biomineralizing complex skeletons in strontium sulfate SrSO4 (i. e. celestine).
Those protists have no (as far as I know) fossil record for the good reason that celestine is soluble in seawater once the organism decayed.
However it has been speculated (e. g. **Bernstein et al. 1992**) that acantharian-derived celestine could be at the origin of the formation of Sr-rich barite.

What is the status of this hypothesis? If this is still considered true, is there a way to differentiate unambiguously acantharian-derived barite from other kind of barite?

This would of course have interesting paleontological implications.

Source:  
Bernstein, R. E., Byrne, R. H., Betzer, P. R., Greco, A. M., 1992. [Morphologies and transformations of celestite in seawater: The role of acantharians in strontium and barium geochemistry](http://www.sciencedirect.com/science/article/pii/0016703792903042). Geochimica et Cosmochimica Acta, 56: 3273-3279.

**Tags:** paleontology, diagenesis, sedimentology, biomineralization

> **Comments:**
> **username_1**: The correct mineral name would be celestine, not celestite. It is the official name recognised by the IMA.  

---

## 0 answers

