You can read more about tartan colors here.
In any case, often as I have been sewing up someone's weathered Gordon kilt, or weathered Black Watch, or weathered Lamont, etc., I have remarked on how nice the gentle browns and greys of the tartan looked. My wife has often made similar comments as she has seen me working on weathered tartan kilts.
Seeing as we both like the colors so much, it is a bit surprising that I have not had a weathered kilt in my wardrobe. Well, that is not entirely true. I do have a MacQuarrie kilt in Dalgliesh's reproduction colors, but the primary color in that tartan is red, and this gives quite a different effect than a primarily green/blue tartan. In the weathered, or reproduction, color scheme, reds fade to a softer "brick" red, while greens fade to brown, blues to grey. It is a very different look.
The only green/blue tartan I have family connections to is the Armstrong (my maternal grandmother's maiden name). But the only colors that are currently commercially produced in this tartan are modern and ancient. And I have a kilt in the modern Armstrong tartan, which I enjoy wearing. Here's a photo of me in my modern Armstrong kilt, standing with Capt. Sir Malcolm MacGregor of MacGregor, and his lovely wife the Lady Fiona MacGregor (nee Armstrong).
Some months ago I decided that there was no real reason I couldn't have the Armstrong done up in weathered colors if I so chose. Just because the larger mills don't keep the tartan you want in stock is no reason not to get your kilt in that tartan. I often have single kilt lengths of non-stocked tartans custom woven for clients, and it really is not that much more in terms of cost.
So I contacted D. C. Dalgleish and asked them to weave 4 yards in the reproduction Armstrong for a box pleated kilt for myself. The fabric arrived a few weeks later (actually, rather quickly -- it can typically take 8 to 12 weeks for a custom weave and I believe I had it in my hands in less than a month). It was beautiful. And it continued to look beautiful sitting in my sewing room for about six months! (Note to all of you in my queue right now "jonesing" for one of my kilts -- I know how you feel!)
Finally, earlier this month, I worked it in to my schedule to make my own kilt. And I am very happy with the results. Because the size of the sett in this tartan is somewhat smaller than typical, it worked out better for me to pleat this kilt (a 4 yard box pleated kilt) to the sett, as opposed to the stripe, as I normally pleat my kilts. This is actually the only kilt I currently own that is pleated to the sett. It's not my preferred style, but I rather like it in this kilt, as it shows the subtlety of the browns and greys in equal proportions. I think it creates a very balanced look.
I've already worn this kilt in to the museum a couple of times, and I'm finding the soft colors very easy to coordinate. I predict this one is going to get frequent wear!