I am a fabricator.

Sunlight will fade quartz countertops of any brand. Dark colors are faded noticably in just a few weeks of direct sunlight. We fabbed and installed Cambria for several years and have replaced kitchens that faded. Kudo's to Cambria for standing behind their product as the replacement was at no cost to the consumer.

A very few granite colors will fade after months or years in direct sunlight (stored outside in full sun.) We have never had a complaint about fading inside a house. The only watch out for the consumer on granite is that their kitchen not be made from one slab that was on the top and others that were buried. Any decent fabricator will make sure of this as a matter of course.

I was planning on quartz for my countertops, and now I am concerned about the fading for the perimeter. There are four windows around the perimeter of my kitchen - are there going to be squares of fading where the windows are? I am going to be using a dark grey color.

Would dark grey or black granite be better? Thanks!

Windows these days have UV blocking coatings that will minimize the fading. But, if you plan on open windows a lot, don't choose a dark quartz.

I had no idea that quartz fades.

I have dark gray Caesarstone on all the counters in my G-shaped kitchen. I have an east-facing window and in the summer the sun shines on my peninsula in the mornings. Not endlessly, not a steady pounding stream of sunlight. An hour or so of moving sunlight. There's been no fading after two summers.

This isn't to say that quartz won't fade, esp. a dark one. But mine gets exposed to sun and seems to have held its original color.

As far as granite fading in the sun, check out the countertops the next time you're in Las Vegas. I've got a picture of a doozy, but I can't find it right now.

Fading shouldn't be an issue for granite or estone properly installed indoors.

would light quartz fade much? Let's say cream?

Here is a fact...

Granite fades in the sun... didn't think it would as much, but...

I have a few slabs sitting outside my shop (I'm a cabinetmaker). My granite guy stores a few at my shop for exposure as I'm on the main drag. We are using one of the slabs for a show kitchen we are building for this year's home shows. The slabs are on racks, held down with straps (it gets windy). The slab ABSOLUTELY faded in the sunlight... it is much darker where the strap was... I'm hoping he can sort it all out...

Some granite slabs are dyed or treated with resin and can't be left in direct sunlight for an extended period. The stone itself never fades. The problem is managed simply by having the top slab in a bundle turned in. I have never had an instance of granite fading in a home. I have had instances of dark quartz colors fading.

Some stone have mineral components that will oxidize and darken over time after they are cut from the block and then polished. Normally the length of time from quarry to market is enough for that oxidation to occur so it only shows up as lighter edges when the stone is processed into countertops. Fabricators have products they use to darken up the edges.

Many granites in residential applications have been treated at the factory with resin. That resin is subject to ultraviolet light degradation. Although interior failures are rare, slabs should not be stored uncovered outdoors. Many stoners knock solid surface for being "plastic" but their industry wouldn't exist without it.

Do Corian and the many other current knock-offs discolor? I have southern exposure windows that bathe the kitchen in brilliant light for several hours a day in the warm months.

"Do Corian and the many other current knock-offs discolor?"

In a residential installation, no. Any UV damage could be easily undone with a refinish.

http://img.archiexpo.com/pdf/repository_ae/96/corian-cladding-108613_1b.jpg