Earlier you mentioned that the grey Reveal has details that people could not have known about 20 years ago. However, the reverse is true. We have a better understanding of what an authentic prop looks like in terms of aesthetic flow, balance, proportions of features, etc.
I've already established that the essence, aesthetic flow, etc. of the DS 20th Century is a very good basis of comparison of facial feature proportions, angles, etc. when compared against the LFL Reveal tour mask. I have other accurate castings that corroborate with the 20th Century, so honestly, it's not a bad baseline. I use the 20th Century due to availability, so other 20th Cent owners can study this themselves.
This comparison you're about to see is challenging because there are various things about the grey Reveal that are proportionately off, and therefore getting a perfect overlay is not possible.
Again, were this a production-related mask, it had to have been based off of something of the UK lineage tree, just as the 20th Century is based off of the same tree.
Lets walk through the discrepancies. This is only a partial list. The numbers I'm going by correspond to the numbers in the image below.
1. Notice the eyebrow as it joins with the bridge of the nose and frown-bump. Not only has this been sanded down and the eyebrow now become sharp, but the angle of the eyebrow now causes it to meet the nose bridge lower than on the 20th Century.
2. The bridge of the nose on the grey Reveal is not as high as the 20th Century.
3. Again, like 1, the left eyebrow has been sanded down, and the brow reduced from a wider thickness to a sharp edge. It also joins the bridge of the nose lower than on a screen-accurate mask.
4. The nose bridge's 3 notches are now more compressed than on the 20th Century. Moreover, there is a decrease in width towards the bottom, which is inconsistent with that found on screen-used masks.
5. Here's where it gets interesting. Pardon the inherited damage on the 20th Century casting, but you can also use any picture of LFL props to corroborate this. The orange line represents material removed. There also appears to be significant sanding of not just the top of the nose but the whole arch of the nose as it rises up towards the nose bridge.
6. The inside nose has possibly been sharpened. The mouthwall on the right of the image appears to have been thickened, and the inside shape is simplified, similar to what you see on a Don Post Classic Action. Scroll back to the top pair of images and notice now how small the nose is and how wide the cheeks are in terms of proportions when you compare the grey Reveal against the 20th Century.
7. This is where things get interesting because of 8. As the whisker leaves the nose and moves outwards, it starts of kind of okay. Towards the nose, there is indication of sanding so the whisker is thinner. But as it moves outwards, it starts to narrow instead of widen. On the screen-used and accurate castings, it crescendos into a swell before swooping down and joining the edge of the cheek. Not so with the grey ROTJ. This can generally be explained by oversanding of this area.
8. This shows either a warpage of the fiberglass or that material was added to widen the face, but in so doing it interrupts the aesthetic flow when viewed from top to bottom. The earlier comparison of the side profile shows the cheek edge on the side being turned from a curve into a straight line, so it's possible this cheek was physically tampered with and re-interpreted. If extra material was indeed added, some excess might be obscuring the whisker (7) and overriding the swell.
There is more. I don't have time for photograph comparison but:
9. The teeth bars depth are inconsistent with that of screen accurate props. You'll have to refer to a 45 degree angle from one of your previous posts. They are extremely shallow towards the top of the bars.
10. The chin triangle on the grey appears to the a reasonably accurate shape, but the positioning is wrong. It's much too close to the edge of the mouth. Don't use the 20th Century as a basis of comparison, as the 20th Century chin triangle is smaller than screen-used (it might have been done on purpose as a tell to distinguish tour masks from production masks).
11. Bottom mouth line on the grey Reveal is slightly curving upward.
12. Mouth on grey Reveal is more symmetrical than the screen-used. As you look at it, the mouth wall has been thickened to achieve this effect.
13. Skull area has been narrowed.
14. Neck has been trimmed significantly.
... and more. And these are in addition to the inconsistencies that have already been discussed.
Hope all this helps. It's not to say this isn't production-related, and perhaps it was something someone tried to salvage. Even if it were a bad casting, the essential aesthetic flows would still have been there. The 20 Century that Darth Stone obtained as a bit beat up due to age and handling but is still quite elegant in shape and consistent with accurate masks. I can't, for any reason, see why someone would oversand the grey Reveal on one hand, and purposefully thicken the mouth and the left cheek (right, as you look at it). In other words, the person who was working on this was removing material in some parts and adding material in others, but for what reason?
If there was ever any direct connection to studio originals, it's been eradicated by whoever had worked on the mask. If the owner is looking for verification among the auction houses, they might tap one of the members of this community who would perhaps provide the same observations. The next point of verification for the auction houses would be establishing the authenticity of paperwork behind this mask, should they even feel the mask could go that far in the auction process.
Over the years, we've seen various individuals and Vader-vendors (eBay, online, etc.) who have had helmets purported to be production-related. A claim is made, and then the burden of disproving it is thrust upon the people to whom the helmet is presented. These are sometimes well-meaning people who have studied props for years or decades and thus spoke from a position of experience. Some have cited that their helmets were unused prototypes. Two Vader vendors made claims that turned out to be utter fabrications. We've had quite some history here, so we'd like to open-mindedly analyze things carefully.
Too much work has been done to convince me beyond a shadow of doubt that this has any connection with the production. And even if it were so, I find no logical reason to re-interpret so much, but because of so many inconsistencies, assuming this ever had connection with the production, the value of the mask is harmed because all the tells that would have verified its originality as a Vader mask are gone.
Now here's the clincher. If the owner were to remove the primer, what would it reveal? It would be interesting to see if material had been added to the mask prior to being shot in primer. If not, then it's a
copy of something that had already been modified.