Recently, I filled a PAB cup in the nearest LEGO store. Among other parts, I also took a lot of light bluish grey 2x2 tiles. The following image shows some of these:

No difference visible from this angle

However, reflected light reveals that the surface of the tiles can be quite different. This image (same parts as above) shows that there are obviously two types of tiles. One with a really smooth surface, with the stud ring on the underside visible from above. And one with a rough surface similar to brushed metal:

enter image description here

I am a bit surprised to see LEGO products with their sub-micrometer precision molds showing such behaviour. Are different production lines mixing here? Have you experienced other parts with different properties that should be the same?


Alexander O'Mara suggested to examine the underside, and indeed there are some patterns. First, the smooth tiles: underside of smooth tiles

Now the "brushed" tiles: enter image description here

You notice the groove above the word LEGO on the smooth tiles that the brushed tiles don't have. The number 3068 is of course the same on both. There is a lot number (?) in the format XX-YY with YY being underlined.

The smooth tiles all have XX-57 with varying XX (right hand side), the brushed tiles all have XX-49 with varying XX (lower side, next to the "3068").

So, what does that mean?


One observation: inside the bottom tube, the surface shows a structure in the smooth tiles, but no structure in the "brushed" tiles. This could mean that the 3068 tile consists of two pieces that are hot-glued together in the process: One part covering the upper surface and sides, and another piece with the bottom tube and inside. The upper, covering part (from which small pieces are stamped out) may itself have an upper and lower side with slightly differing roughness. Maybe the production process doesn't prefer which side is up, so sometimes a rough side can be seen, and sometimes not. This is only a theory.

Can someone point towards an answer?

  • 2
    Do the undersides between them distinguishable at all? I wonder if there are different versions of the mold. Nov 15, 2017 at 3:46
  • Good point. I will have a closer look and update the question today.
    – Metalbeard
    Nov 15, 2017 at 11:11
  • The XX-XX numbers I believe identify the mold that made the piece (so if they get defective ones, they know which mold has a problem). Possibly The second half of the number identifies a version of the mold? I wonder if perhaps one version is/was used for painted or sticker pieces (I know it seems weird to have a different piece for stickers, but I've seen them provide smoother roof tiles for stickers, sometimes with a mix in the same set). Nov 16, 2017 at 19:56
  • Do you mean slope bricks or tiles that are used on roofs?
    – Metalbeard
    Nov 17, 2017 at 7:35
  • I mean the sloped bricks. Nov 17, 2017 at 8:11

1 Answer 1


From TLG Customer Service (emphasis added by me for one possible explanation):

I truly appreciate that you sent this to us so that we could see the variation in the parts. Being able to see the numbers on the inside was very helpful!

We haven't had any reports about quality issues with this element for any of the pressings. I've actually taken the link you provided and, as you know, the LEGO® Quality Team takes the quality of our products very seriously, and our team will now be able to look at these images in the post and make further evaluations. It could be that the mould was changed and the new mould hasn't worn smooth yet but I can't say for certain that that would be the cause of the variation in the texture on the top of the tile.

Please make sure the user doesn't delete the post so that our Quality Team can take a look.

Thank you again for passing this important post along to us. We really appreciate it!

  • 2
    I didn't know that TLG is so responsive to these kind of questions. I assume that you will post the final results? Does TLG even have a user here??
    – Metalbeard
    Nov 17, 2017 at 20:33
  • 1
    I'll definitely update this answer if I hear any more details. TLG takes quality very seriously. I've never seen anyone post here officially representing TLG, but I'd certainly be happy to see that. It's tricky on their end, as there is significant media training that employees need to go through to speak publicly for the company.
    – jncraton
    Nov 17, 2017 at 20:58
  • Have you heard any news from TLG?
    – Metalbeard
    Dec 2, 2017 at 20:20
  • @Aziraphale Nothing since I've posted this, I'm afraid.
    – jncraton
    Dec 2, 2017 at 20:47
  • It seems that TLG didn't come to a conclusion, or it was not important enough to get back to you.
    – Metalbeard
    Dec 15, 2017 at 23:13

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.