Here's a working definition of granite

This post ran originally on 13 October 2008

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The term granite, as it's used commercially, is a bit of a generic term. Now I'm not a geologist but I do have an understanding of the fundamental geology that goes into the dimensional stone that ends up in peoples' homes.

Granite's generally accepted to be an igneous rock composed primarily of silica that's formed in the mantle of the earth as magma gets squeezed between cracks in the earth's crust. As a liquid at that point, the magma tries to rise to the surface. It cools very slowly and under very high pressure then forms what are called batholiths --essentially huge domes that lie below the surface of the earth. These large formations are exposed later through the actions of erosion and thrust faulting. Due to the high pressure under which the magma cooled, the component minerals in it (quartz, feldspar, aluminum oxide, iron oxide, etc.) can crystallize. That crystallization is what makes granite granite.

I bring that up because of this granite right here, commonly called Baltic Brown.

You can see from this close up that Baltic Brown has circular crystals in it. They are in varying sizes but most of them are about two inches in diameter. Those round crystals are made from potassium feldspar and they formed about a gazillion years ago as some magma cooled underneath what is now Finland.

About eight years ago I got into it with a salesperson at a granite wholesaler who claimed that those round shapes were the remains of a stand of young trees that were run over by a lava flow and got fossilized in the process. People who don't understand what they're selling are a pet peeve. Claiming to have fossils in a slab of granite goes beyond not knowing and crosses the line into the idiotic. I don't expect granite salespeople to be able to rattle off the names of the component minerals that make up what they're selling, but some basic knowledge is most definitely in order.

Granite that ends up as counters gets cut into slabs and polished. From the cut stone, you get a really nice cross section of the crystal structure of a particular granite. Those crystals are where granite gets its sparkle and depth. A granite that was left to its own devices as it cooled and formed over the millennia will have a pretty regular pattern and color.

But when granite's actually moving as it cools, or if it runs into water, all sorts of things happen to it. A lot of times granite will run into other kinds of rock as it moves, so it will have incursions of schist and skarn and a host of other materials in it. A lot of times water will make iron oxide gravitate into cracks in the rock. Every component mineral in a granite has its own characteristics and reactions and that non-uniformity is at the root of granite's appeal. The slab below has incursions as well as lines of iron oxide in it.

It's an interesting stone as a stone, but it's a lot to try to pull off in a kitchen counter. I mean, it's pretty loud. Something like that I'd like to hang on a wall to admire. It tells a really compelling story but it's not something I'd want to see in one of my kitchen projects.

Patterns like that granite above are still pretty popular though that popularity has crested and is starting to wane. People are starting to look for other materials to use as counters and that's what I'll be writing about all week. Woo-hoo!

But in the meantime, if you like granite then get granite. Don't believe the stories of its propensity to stain or crack or even be radioactive. Almost every negative you hear about granite is chatter generated by a competitive marketplace. I have never actually seen someone stain or crack a granite counter. Nor have I ever heard of someone who had to reseal their counters. The radon hype is yet another non-story generated by the solid surface people to prop up their decidedly inferior products. Granite is harder than just about anything it will come in contact with and it will continue to look as good as it did the day it went in for the rest of the time you have it.

But let's look at some options anyhow. Tomorrow's going to be marble and the metamorphics.

Revisiting the rocks in my head

This post ran on 13 October 2008 originally
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Rocks are divided into three categories: sedimentary, metamorphic and igneous. A lot of times these three classes are referred to as phases because each class can morph into each of the other classes over long periods of time. But that's can morph, it isn't automatic.

In English, those three classes can be pretty broadly defined like this: sedimentary rocks are formed by compacted sediment, metamorphic rocks are rocks that are transformed by heat and pressure after they're already formed and igneous rocks are formed by cooling magma. Some examples of sedimentary rocks are limestone and travertine. Some metamorphic rocks are marble, quartzite, soapstone and slate. Finally an igneous rock that's in a lot of peoples' homes is granite.

In the chart above, there's a delineation made between intrusive and extrusive igneous rock. Intrusive means that a formation of igneous rock rises into the earth's crust but doesn't break the surface. Not breaking the surface results in a very particular crystal structure. Extrusive igneous rock breaks the surface and cools quickly when not under pressure. This results in a different structure even if the magma has the same composition.

So there's my breakdown of the three classes of rock. There are examples of all three classes that end up being pressed into use by humanity and I'll be spending some time explaining them further. First up will be granite.

A mid-century modern prosthetic leg

This post ran on 22 September 2008 originally.
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I came across this on Apartment Therapy this week and I couldn't pass it up.

I love the work of Charles and Ray Eames as I've said before on many occasions. In 1956, the Eames' released their Eames Lounge and Ottoman through Herman Miller. Herman Miller still produces them now, but in 1956, the Eames/ Herman Miller combination hit pay dirt and released an instant classic. This chair is a design icon for obvious reasons. Designers go ape over it still and it remains as popular now as it was at the time of its unveiling.


An industrial designer named Joanna Hawley took her inspiration from the Eames Lounge and Ottoman and used that inspiration to design a prosthetic leg while she was a design student at Carnegie Mellon University. Hawley partnered up with Kayhan Haj-Ali-Ahmadi, a pre-med student. Kayhan's knowledge of anatomy and Joanna's design skills combined to terrific effect and the fruit of their partnership speaks for itself.
When I think of prosthetic limbs, If I think of prosthetic limbs, the idea that they should be beautiful never occurs to me. When it comes to medical devices, I always assume that function trumps form every time. Who says they can't work together? Clearly, not Joanna Hawley.


In her own words and from her website:

Prosthetics generally lack humanity, style and grace. Often, they look much like landing gear and make the wearer uncomfortable, self aware, and sometimes depressed. By channeling the Eames' use materials and iconic style, we designed a leg with Steve McQueen in mind. We sought to convey a creative use of positive and negative space, a balance of materials and a reflection of the wearer.

I corresponded with Joanna Hawley a bit the other day and I asked her why a prosthesis? Here's what she had to say:

Today's generation is faced with the Iraqi war, particularly the reality of soldiers coming back without limbs. Diabetes is also the leading cause of amputees in America, which is a little known fact. Finally, as an Industrial Designer, its my job (and passion!) to think of ways to improve people's lives. All these reasons simply rolled into one very intense and exciting project. I've always been a huge fan of Ray and Charles Eames (as you can probably tell by the rest of my work) and I wanted to give this prosthetic a very eye-catching aesthetic. I know veneering can be polarizing, but so far people seem really excited by the possibilities. And really, that's what the point of the project was, to identify the possibilities in the future of prosthetics.

Get this woman an award.

An even thousand

Charlestown Primary School

This is my one thousandth post. Thank you one and all. After a thousand posts, I think I deserve a short break. So for the next couple of days I'm going to re-run some of my archived posts while I take the weekend off. I'll be back with new content bright and early Monday morning.

Thanks again to one and all. It's your feedback, your comments, your e-mail and your good humor that keeps me plugging away. See you Monday.

Color perception Thursday

I lifted this image from the brilliant Richard Wiseman. It illustrates another cool quirk about human eyes and their ability to perceive color.

Click on the image below and it will start its animation. Stare at the black dot in the center of the photograph.

Did you see it?

When the image changes, it's a black and white photograph, but your eyes should see it as a normal color image for a couple of seconds until your eyes adjust. Go back and try it again if you missed it.

What's happening there is what's called a negative afterimage. When you stare at something long enough, the cone cells in your retina adapt to the image and stop processing new information. They go into a feedback loop that continues to send information to your brain that's a copy of the information they've already sent.

Once the image they're perceiving changes, it takes them a couple of seconds to adapt to the new information. In the lag time, your brain can't make any sense out of the signals that it's getting so it more or less makes up what it expects to be there.

Afterimages are why you can't see colors accurately if you stare at them for too long.

Afterimages don't just work on still photos either. This one moves and it's cool beyond description.



Human eyes and human brains are amazing machines but they are fallible. It's important to know where the chinks in the armor are.