<p>thank you for your interest in the article. I'm the lead author on this paper (Shipway) and I happened to come across your post when looking through all the media stories on this animal. </p>

<p>To answer your question; yes, you're right, the rock is a calcareous sandstone. It was easy to split, partly because it is a naturally soft rock and partly because the shipworms had weakened the structure.</p>

<p>Hope that answered your question.</p>

CC BY-SA 4.0
2019-06-19T13:40:38.670Z
Welcome to Stack Exchange and thank you for stopping by! It's fascinating stuff for sure. The paper [A rock-boring and rock-ingesting freshwater bivalve (shipworm) from the Philippines](https://royalsocietypublishing.org/doi/10.1098/rspb.2019.0434) mentions various limestones but doesn't say anything about sandstone. But I did just now notice that the NYTimes article does mention sandstone.
uhoh
CC BY-SA 4.0
2019-06-19T12:26:03.630Z
2019-06-19T12:26:03.630Z
ShipwayR
<p>The New York Times article <a href="https://www.nytimes.com/2019/06/18/science/shipworm-rocks-sand.html" rel="noreferrer">This Creature Eats Stone. Sand Comes Out the Other End.</a> describes the shipworm <em>Lithoredo abatanica</em>, an organism that appears to "eat solid rock".</p>

<p>It links to the item in Science <a href="https://www.sciencemag.org/news/2019/06/rock-eating-worm-could-change-course-rivers" rel="noreferrer">This rock-eating ‘worm’ could change the course of rivers</a> which then links to the YouTube video <a href="https://youtu.be/K220SUWJ73w" rel="noreferrer">Snippet: Shipworms that eat rocks</a>.</p>

<p>The video shows how easily this rock can be split apart.</p>

<p>The rock was taken from the bottom of the <a href="https://en.wikipedia.org/wiki/Abatan_River" rel="noreferrer">Abatan River</a> on Bohol Island, in the Philippines.</p>

<p><strong>Question:</strong> Is it possible from the images, descriptions, and video to say something about this rock? Is it a kind of sandstone? It looks fairly loosely held-together and porous.</p>

<hr>

<p>Images from <a href="https://www.nytimes.com/2019/06/18/science/shipworm-rocks-sand.html" rel="noreferrer">NYTimes</a>:</p>

<p><img src="https://i.sstatic.net/mjmb5.jpg" alt="Lithoredo abatanica, from inside a piece of rock"></p>

<p><strong>above:</strong> Lithoredo abatanica, from inside a piece of rock. CreditM arvin A. Altamia and Reuben Shipway (click for full size)</p>

<p><strong>below:</strong> Two large burrows in rock made by shipworms. Credit Marvin A. Altamia and Reuben Shipway (click for full size)</p>

<p><img src="https://i.sstatic.net/YoGJE.jpg" alt="Two large burrows in rock made by shipworms"></p>

<petrology><paleontology>
What kind of rock is this being eaten by a rock-eating worm?
uhoh
# What kind of rock is this being eaten by a rock-eating worm?

(Asked by: username_0 on 2019-06-19)

The New York Times article [This Creature Eats Stone. Sand Comes Out the Other End.](https://www.nytimes.com/2019/06/18/science/shipworm-rocks-sand.html) describes the shipworm *Lithoredo abatanica*, an organism that appears to "eat solid rock".

It links to the item in Science [This rock-eating ‘worm’ could change the course of rivers](https://www.sciencemag.org/news/2019/06/rock-eating-worm-could-change-course-rivers) which then links to the YouTube video [Snippet: Shipworms that eat rocks](https://youtu.be/K220SUWJ73w).

The video shows how easily this rock can be split apart.

The rock was taken from the bottom of the [Abatan River](https://en.wikipedia.org/wiki/Abatan_River) on Bohol Island, in the Philippines.

**Question:** Is it possible from the images, descriptions, and video to say something about this rock? Is it a kind of sandstone? It looks fairly loosely held-together and porous.

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Images from [NYTimes](https://www.nytimes.com/2019/06/18/science/shipworm-rocks-sand.html):

![Lithoredo abatanica, from inside a piece of rock](https://i.sstatic.net/mjmb5.jpg)

**above:** Lithoredo abatanica, from inside a piece of rock. CreditM arvin A. Altamia and Reuben Shipway (click for full size)

**below:** Two large burrows in rock made by shipworms. Credit Marvin A. Altamia and Reuben Shipway (click for full size)

![Two large burrows in rock made by shipworms](https://i.sstatic.net/YoGJE.jpg)

**Tags:** petrology, paleontology


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## 1 answers

### Answer by username_1 on 2019-06-19. Score: 15 | Accepted answer

thank you for your interest in the article. I'm the lead author on this paper (Shipway) and I happened to come across your post when looking through all the media stories on this animal.

To answer your question; yes, you're right, the rock is a calcareous sandstone. It was easy to split, partly because it is a naturally soft rock and partly because the shipworms had weakened the structure.

Hope that answered your question.

> **Comments:**
> **username_0**: Welcome to Stack Exchange and thank you for stopping by! It's fascinating stuff for sure. The paper [A rock-boring and rock-ingesting freshwater bivalve (shipworm) from the Philippines](https://royalsocietypublishing.org/doi/10.1098/rspb.2019.0434) mentions various limestones but doesn't say anything about sandstone. But I did just now notice that the NYTimes article does mention sandstone.  

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