I was actually going to post a question about what the difference was in certain shades of blue (like Maersk blue compared to medium azure) but instead I found this image comparing most of the blues to blue-greens Lego has used over the years. I find it interestingly helpful and thought you may too.

>Lego Blues by cjedwards47, on Flickr

(from left to right)

• Sand blue
• Dark turquoise
• Light aqua
• Bright light blue
• Medium blue
• Maersk blue
• Medium azure
• Dark azure
• Blue
• Dark blue

And the tiles are Sky blue, which appears to be the closest match to Medium azure.

Fantastic, thanks! How did you know I was going to be going through a huge pile of used Lego this week, some of it in old blues?! :-)

That's pretty cool.  

 

Someone should do the same with old grey, new bluish grey ("bley"), and the dark ones maybe.

Fantastic, thanks! How did you know I was going to be going through a huge pile of used Lego this week, some of it in old blues?! :-)

You know how it goes, us wierdos are psychically linked. Actually I was going to post a question of "Is Maersk blue the same as Medium Azure?" since I had thought they appeared similar but instead I did a little search and it seems they are not. I then thought of sharing my findings with everyone!

 

Someone should do the same with old grey, new bluish grey ("bley"), and the dark ones maybe.

Ask and you shall receive....

>The Old Grey LEGO Challenge by TheBricks, on Flickr

This color chart has been helpful with all the random slight differences...

 

I never knew that there were this many types of Blue and Gray colors. I have a lot of different pieces that I do not know which color they are. This will really help me.

I never knew that there were this many types of Blue and Gray colors. I have a lot of different pieces that I do not know which color they are. This will really help me.

For grey it's more that they switched than they have lots of colors. In 2004, fleshie minifigs started showing up in licensed themes (started off a year earlier with the NBA guys). Then they switched both greys to be a bit more bluish and IMO more attractive. As for why? I dug this out: (WARNING: LONG POST)

Subject: Color Change background

First off, I apologize for bringing this issue up again, but a promise is a promise. I said I would deliver more background info on the color change, and here it is. In an effort to reduce the almost certain flood of responses to this post, please understand that I am only posting the story, and won

As an older adult new to lego other than lego trains I wanted to thank you for your posts.  You clarified a few questions I had.