Ichthyosaur piece

[dhiggi]

I have seen this for sale, however the seller states that they don’t know if it is real or a replica. I’m thinking it might be worth taking a risk on, but the air bubbles in the bottom are a red flag. It’s clearly another layer to the top so I suppose it could just be something added to the fossil to strengthen the piece. I’m also thinking that such a piece wouldn’t usually be worth making a replica of. What are your thoughts on this; worth the risk at a low price?

[pachy-pleuro-whatnot-odon]

Hard to say: the bone definition is excellent and I think the bone texture visible in the third photograph might be difficult/too labour-intensive to reproduce accurately if this were a replica. But at the same time the bubbles do look a bit suspect; there's this light gray band or line running between the top layer containing the bones and the one(s) underneath; the matrix has a very smooth look to it; and I've seen specimens for sale with this same finish that I could've sworn were real fossils but were sold as replica's (I didn't buy any of these, so, unfortunately, haven't been able to inspect them and draw my own conclusions).

 

I'm still leaning towards this piece being authentic, however. For, while I'd need to see the other edges of slab to see if the light gray line continues, I think it's a discolouration rather than filler, since in the one photograph it's most clearly visible in, it tapers out to the right and has been cut in the same shape and with the same type of fracture as the rest of the block. I thus believe the slab to be one piece, moreover an actual piece of shale, as the damage visible on it - e.g., the missing edge and corner and pitting on the third photograph - seems natural for such slabs. This, then, comes in addition to the aspects of bone preservation that I started my post out with.

 

All the same, we're left with the bubbles on the bottom and the high-gloss finish. However, this, I suspect, is due to the varnish that was applied to the specimen. For pieces from the Posidonia Shale have traditionally been treated with some kind of varnish to seal them and variedly prevent flaking and disintegration of the oft fragile fossils as well as stop pyrite decay. I myself have often used a transparent acrylic crafts seal that, if applied to areas not fully dried, will form little air bubbles like those on the bottom of this slab. Such varnish may also cause occasional discolouration if not applied evenly (think the banding discussed above), as well as slight flaking, as can be seen in the discoloured splotches underneath the vertebra in the third photograph. Other reasons to think the bubbles here are from a consolidant/varnish rather than from a casting-process are 1) that the base is discoloured around its edges, hinting at that unequal application and drying of a varnish; 2) bubbles can only be seen on the underside and nowhere else; and 3) varnishes can give a fossil a bit of a plastic-y shine and smoothed appearance.

 

While I don't think the same acrylic craft seal was used as I use myself (as mine deepens the colours a bit as well), I think it's likely that paraffin may have been used. This was a common cheap varnish applied to fossils back in the 1980s and '90s and gives pieces a bit of a waxy feel and gloss. This also gives you a point in time as to when the specimen may have been found.

 

I'm not saying that I'm a 100% sure this piece is authentic, but I do think in all likelihood it is.

[dhiggi]

Big help @pachy-pleuro-whatnot-odon, many thanks 

[Ludwigia]

My gut feeling tells me that this is a replica and I've seen a lot of these things and had them in my hands for comparison. The color composition is too uniform in my opinion.

[Fossildude19]

I would stay away from this, unless it is cheap -  I see what appear to be air bubbles in the front of the piece as well.

Upper left and lower left.

 

 

[pachy-pleuro-whatnot-odon]

2 minutes ago, Fossildude19 said:

I would stay away from this, unless it is cheap -  I see what appear to be air bubbles in the front of the piece as well.

Upper left and lower left.

 

Not sure whether these are air bubbles, the photographs are just too poor quality to tell. They could also be the result of poor preparation, which would coincide well with the sloppy application of the varnish in my hypothesis. May be @belemniten could chip in with his opinion...

[Fossildude19]

 

 

 

[Ludwigia]

Check this out for comparison.

[Fossildude19]

At the very least, I would ask for better pictures - close ups - of the circled areas.

[pachy-pleuro-whatnot-odon]

1 minute ago, Fossildude19 said:

At the very least, I would ask for better pictures - close ups - of the circled areas.

 

That I agree. However, while I did spot the areas you pointed out, the issue I have with them is that they show up white in positive, suggesting that they're pits, not bubbles, especially since the bubbles at the bottom show up dark, rather than white. That these white spots are indeed depressions rather than elevations can moreover be seen in what appears to be a coracoid bone on the bottom right. Here you'll find what appears to be a series of scratches, all in white, next to a bunch of - what I take to be - pits.

 

As another line of evidence for these being depressions and thus not bubbles I'd like to refer to Roger's own beautifully prepared ichthyosaur specimen:

 

 

Not to undermine the excellent skill with which this specimen was prepared, you will, however, see similar light-coloured spots on the tiny bit of bone on the edge, bottom centre, some of the ribs to the bottom right, and variedly along the top left edge as well. As such, I consider this either natural damage or damage that occurred during the preparation process, different from bubbles formed by casting.

 

 

I'm thus not entirely convinced OP's specimen is a replica, though I will say that I find such pieces incredibly difficult to evaluate...

[dhiggi]

Thanks for the input everyone. Here’s some more pics that might hopefully shed a bit more light…

[JohnJ]

Looks like a replica to me 

[pachy-pleuro-whatnot-odon]

Well, with these new photographs I've grown more convinced that this is authentic. The bubbles on the bottom look like holes in a separate layer to me, like I'd expect from a veneer of a thick varnish. But most convincingly I find the bone texture seen on the sides in the third photograph of the new batch, especially the rib that seems to be poking through the side towards the base to the slab. But, again, I might be completely off...

 

Anyway, for the small amount asked for it I think it might be worth the risk,  just to check it out. If worst comes to worst it's just going to be a rather decent replica, in the best case a nice specimen 

[Fossildude19]

[dhiggi]

I have requested better quality close ups of the sides. I’ll post them if I receive any

[Auspex]

27 minutes ago, JohnJ said:

Looks like a replica to me 

Yup; a cast. All the evidence is there. If it is priced accordingly, and is desired as a decorative piece, fine. But if you want a real fossil specimen, keep looking.

[Ludwigia]

Now that I've seen the new photos, I'm convinced that this is a cast. I'm afraid that pachy is a minority of one here.

[dhiggi]

Had these from the seller

[Fossildude19]

 

 

 

 

 

 

[belemniten]

Thats a really weird piece. I would definitely stay away of it.

 

Based on the first three pictures, I would have said it is original. But really badly prepared and set on a plate made of a strange material.

With the additional photos from the side, I am quite certain that it's a replica. Especially with the last pictures. I can't see any bone material there, although the visible bump is probably the place where a cross section of a vertebra should be recognisable. 

[pachy-pleuro-whatnot-odon]

5 hours ago, Fossildude19 said:

 

When I checked the last batch of photographs this was on my mobile phone. Now that I'm back home and can take a better look at them I agree, this is a replica. As Tim and Sebastian rightly point out, you should be able to see the bone in cross-section at the edges of the slab, which is definitely not the case here, even if in some places some changes in texture and colour have been applied to suggest the bone in cross-section. I especially find the cross-section of the vertebra misleading in this respect, as it has been painted in a slightly different colour (which matches some bone preservation from the Posidonia Shale) and even has different texture on the left hand side. All the same, however, the colouration is incomplete on the right, where the vertebra has been painted the same colour as the supposed matrix. Thus, while I believe the suggestion of a crushed vertebra is there, there are some tiny things wrong with it that give the specimen away as replica.

 

3 hours ago, Fossildude19 said:

 

 

Similarly, the layering of the slab itself seems very odd and unnatural, and has probably been crafted on.

 

3 hours ago, Fossildude19 said:

 

One thing I still believe to hold true, though, which is that the bottom is made out of a different material, some kind of varnish maybe, or a material to protect furniture from being scratched by the base of the replica, which the bubbles identified originally actually being little puncture holes through this layer. This, however, is uninformative to the authenticity of the piece.

 

As such, it's indeed probably best to stay away from this piece, although, as said, it would still make a decent replica!