# Is this a fossil or just an odd rock? **URL:** \ **Category:** Factual Questions\ **Created:** [September 14, 2022, 11:45pm UTC](https://boards.straightdope.com/t/is-this-a-fossil-or-just-an-odd-rock/971591 "2022-09-14T23:45:07Z")\ **Posts on this page:** 12\ **Page:** 1
**Author:** ![FloatyGimpy](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/floatygimpy/32/7750_2.png) [@FloatyGimpy](https://boards.straightdope.com/u/FloatyGimpy)\ **Post date:** [September 14, 2022, 11:45pm UTC](https://boards.straightdope.com/t/is-this-a-fossil-or-just-an-odd-rock/971591/1 "2022-09-14T23:45:07Z")
Click on the pictures to see very enlarged image. It’s quite heavy for its size and is very sparkly in the sun. Something seems to be starting to bulge out the underside of it. [![Imgur](https://live.staticflickr.com/65535/52358749284_0d937b458e_b.jpg "IMG\_3052") ](https://www.flickr.com/photos/56821557@N06/52358749284/in/dateposted-public/) [![Imgur](https://live.staticflickr.com/65535/52358856280_edcc686e73_b.jpg "IMG\_3050") ](https://www.flickr.com/photos/56821557@N06/52358856280/in/dateposted-public/) [![Imgur](https://live.staticflickr.com/65535/52358435096_49547fc3bb_b.jpg "IMG\_3054") ](https://www.flickr.com/photos/56821557@N06/52358435096/in/dateposted-public/) [![Imgur](https://live.staticflickr.com/65535/52358856740_55d3322e63_b.jpg "IMG\_3055") ](https://www.flickr.com/photos/56821557@N06/52358856740/in/dateposted-public/) ---
**Author:** ![OldGuy](https://avatars.discourse-cdn.com/v4/letter/o/3bc359/32.png) [@OldGuy](https://boards.straightdope.com/u/OldGuy)\ **Post date:** [September 14, 2022, 11:51pm UTC](https://boards.straightdope.com/t/is-this-a-fossil-or-just-an-odd-rock/971591/2 "2022-09-14T23:51:14Z")
I believe those are minerals veins, probably of silica. They are more resistant than rest of the rock together, so you get less weathering. ---
**Author:** ![DrDeth](https://avatars.discourse-cdn.com/v4/letter/d/b487fb/32.png) [@DrDeth](https://boards.straightdope.com/u/DrDeth)\ **Post date:** [September 15, 2022, 12:21am UTC](https://boards.straightdope.com/t/is-this-a-fossil-or-just-an-odd-rock/971591/3 "2022-09-15T00:21:14Z")
I do not think that is a fossil, but it is still cool. ---
**Author:** ![MrDibble](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mrdibble/32/114_2.png) [@MrDibble](https://boards.straightdope.com/u/MrDibble)\ **Post date:** [September 15, 2022, 5:08am UTC](https://boards.straightdope.com/t/is-this-a-fossil-or-just-an-odd-rock/971591/4 "2022-09-15T05:08:26Z")
Not a fossil. Looks like some kind of igneous/metamorphic rock with quartz veining. Really hard to tell what it is when only seeing the weathered surface. ---
**Author:** ![Isilder](https://avatars.discourse-cdn.com/v4/letter/i/cc9497/32.png) [@Isilder](https://boards.straightdope.com/u/Isilder)\ **Post date:** [September 15, 2022, 5:36am UTC](https://boards.straightdope.com/t/is-this-a-fossil-or-just-an-odd-rock/971591/5 "2022-09-15T05:36:18Z")
If its sedimentary, its not impossible to have fossils in it…But its not the prime sort of sedimentary rock for fossils. You want shale, mudstone and that sort of thing… that would still be soft and crumbly… An igneus or metamorphic wouldn’t have fossils. The lines are not due to fossil inclusions, its due to altered mineralisation of the rock itself… the deposits crack it and glue it back together too. I think its rock due to being sedimentary, it was first layed down as a bunch of sediments (sand, dust,silt, and pebbles ?) and its since concreted… just turned solid due to mineral migration processes. The smoother dark side is black due to minerals too, its not due to a giant leaf or layer of moss or anything biological being fossilised. The minerals in the dark outside layer may be due to very much more recent activity, eg while this stone is lying on the surface level, rather than the slower older mineralisation of the cracks which occurred when it was still underground. ---
**Author:** ![CairoCarol](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/cairocarol/32/3825_2.png) [@CairoCarol](https://boards.straightdope.com/u/CairoCarol)\ **Post date:** [September 15, 2022, 6:24am UTC](https://boards.straightdope.com/t/is-this-a-fossil-or-just-an-odd-rock/971591/6 "2022-09-15T06:24:15Z")
Where did you find the rock? ---
**Author:** ![CalMeacham](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/calmeacham/32/35_2.png) [@CalMeacham](https://boards.straightdope.com/u/CalMeacham)\ **Post date:** [September 15, 2022, 11:35am UTC](https://boards.straightdope.com/t/is-this-a-fossil-or-just-an-odd-rock/971591/7 "2022-09-15T11:35:25Z")
As noted, the veins appear to be harder rock that resists weathering more, so they stand out and resemble something organic. Such deceptive rock formations are so common and so frequently mistaken for fossils that they have a name – _pseudofossils_ Some are extremely convincing. I certainly found more than my share as a kid when I went out prospecting for fossils, and was then extremely disheartened when I realized the truth. When I finally did find fossils, they were unmistakable, and not at all what I had suspected. They were bryozoans, a class of fossil and organism I had never before heard of. > **[Pseudofossil](https://en.wikipedia.org/wiki/Pseudofossil)** > > Pseudofossils are inorganic objects, markings, or impressions that might be mistaken for fossils. Pseudofossils may be misleading, as some types of mineral deposits can mimic lifeforms by forming what appear to be highly detailed or organized structures. One common example is when manganese oxides crystallize with a characteristic treelike or dendritic pattern along a rock fracture. The formation of frost dendrites on a window is another common example of this crystal growth. Concretions are so... > **[Bryozoa](https://en.wikipedia.org/wiki/Bryozoa)** > > See text. > Ectoprocta (Nitsche, 1869) (formerly subphylum of Bryozoa) > Bryozoa (also known as the Polyzoa, Ectoprocta or commonly as moss animals) are a phylum of simple, aquatic invertebrate animals, nearly all living in sedentary colonies. Typically about .mw-parser-output .frac{white-space:nowrap}.mw-parser-output .frac .num,.mw-parser-output .frac .den{font-size:80%;line-height:0;vertical-align:super}.mw-parser-output .frac .den{vertical-align:sub}.mw-parser-output .sr-only{border:0;clip:... ---
**Author:** ![MrDibble](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mrdibble/32/114_2.png) [@MrDibble](https://boards.straightdope.com/u/MrDibble)\ **Post date:** [September 15, 2022, 12:22pm UTC](https://boards.straightdope.com/t/is-this-a-fossil-or-just-an-odd-rock/971591/8 "2022-09-15T12:22:39Z")
> [@Isilder](#): > > An igneus or metamorphic wouldn’t have fossils. That’s not exactly true, they’re rare, and highly dependent on the degree of metamorphism but e.g slates can host fossils, I’ve pulled trilobites and brachiopods out of slate beds myself, and more than one _Lagerstätten_ is slate-hosted, like the [Hunsrück Slate - Wikipedia](https://en.wikipedia.org/wiki/Hunsr%C3%BCck_Slate). Then, there’s volcanic ash beds, those also [can host fossils](https://en.wikipedia.org/wiki/Ashfall_Fossil_Beds) and are somewhere between igneous and sedimentary. ---
**Author:** ![FloatyGimpy](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/floatygimpy/32/7750_2.png) [@FloatyGimpy](https://boards.straightdope.com/u/FloatyGimpy)\ **Post date:** [September 15, 2022, 2:10pm UTC](https://boards.straightdope.com/t/is-this-a-fossil-or-just-an-odd-rock/971591/9 "2022-09-15T14:10:57Z")
Thank you for the feedback. I guess it’s probably just veining wearing away at a different rate than the rest of it. I am tempted to crack it open though. Here is a fossil I found last year - Inoceramus vancouverensis. Almost all of my finds are from Englishman River on Vancouver Island. [![Imgur](https://live.staticflickr.com/65535/51363928600_e28880692f_b.jpg "Inoceramis Vancouverensis") ](https://www.flickr.com/photos/56821557@N06/51363928600/in/dateposted-public/) This is a plummet I found in the river: [![Imgur](https://live.staticflickr.com/65535/51424655277_714eaaa918_b.jpg "Plummet") ](https://www.flickr.com/photos/56821557@N06/51424655277/in/dateposted-public/) ---
**Author:** ![MrDibble](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mrdibble/32/114_2.png) [@MrDibble](https://boards.straightdope.com/u/MrDibble)\ **Post date:** [September 15, 2022, 2:24pm UTC](https://boards.straightdope.com/t/is-this-a-fossil-or-just-an-odd-rock/971591/10 "2022-09-15T14:24:18Z")
Not seeing the _Inoceramus_ in that, tbh, but I’ll take your word for it. Also, you have it mislabeled as an ammonite in the gallery. ---
**Author:** ![FloatyGimpy](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/floatygimpy/32/7750_2.png) [@FloatyGimpy](https://boards.straightdope.com/u/FloatyGimpy)\ **Post date:** [September 15, 2022, 2:29pm UTC](https://boards.straightdope.com/t/is-this-a-fossil-or-just-an-odd-rock/971591/11 "2022-09-15T14:29:06Z")
I took it to these guys who identified it for me. Thank you, I forgot that I originally thought it was an ammonite so I’ve changed it on flickr. > **[Comox Valley Fossil Adventures | Education | Courtenay](https://ca.locale.online/comox-valley-fossil-adventures-1620614128.html)** > > Comox Valley Fossil Adventures in Courtenay - Contact details, Address Map, Photos, offers, Real time Reviews and Ratings ---
**Author:** ![MrDibble](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mrdibble/32/114_2.png) [@MrDibble](https://boards.straightdope.com/u/MrDibble)\ **Post date:** [September 15, 2022, 2:49pm UTC](https://boards.straightdope.com/t/is-this-a-fossil-or-just-an-odd-rock/971591/12 "2022-09-15T14:49:45Z")
Yeah, I didn’t mean I doubted the ID, just that I’m not seeing the bivalve there. It’s definitely _something_.