Tag Archives: smithsonian

Fun science: more crystals!

Months ago, I posted about the collection of crystals and minerals at the Smithsonian Natural History Museum. Well, I went again, this time armed with a nicer (and heavier!) camera, and below are a few of the finds.SONY DSC

Quartz: quartz is a very common type of type of mineral (the second most common after feldspar), made up of silicon and oxygen. This variation is called agate. I used to buy agate slices as a kid, but the Smithsonian’s are slightly fancier.


Another example of quartz. This one arose in a piece of petrified wood. I like this one because it looks like a painting of a setting sun behind a row of pine trees–almost Japanese.


Malachite with azurite: both malachite and azurite are compounds of copper with oxygen, carbon, and hydrogen. The two differ only in the ratios. By geological standards, this rock formed somewhat quickly. We can tell this because the crystals are numerous and small. Single, large crystals form more slowly. This is why you should make ice cream at low temperatures, because when you freeze it quickly, many tiny crystals form, producing a better texture.


Pyrite: As you may see, pyrite, or fool’s gold, has a cubic crystalline structure. Pyrite is composed of iron and sulfur.



Calcite with duftite inclusions: Calcite is known for its optical properties such as birefringence. It was used as a material for gun sights in World War 2. Duftite is a compound of lead, copper, and arsenic. It is the duftite that gives the distinctive green color. I think of this as the kiwi mineral, as it even has the seeds.


Udvar-Házy Air & Space Museum

Did you know there are actually two Smithsonian Air and Space museum locations? There is one on the National Mall in Washington, DC, and a second in Virginia near Dulles Airport, called the Udvar-Házy Center. The Udvar-Házy location is an enormous hangar filled with historically significant aircrafts, aircraft parts, and spaceflight artifacts, including such highlights as the Enola Gay, an SR-71 Blackbird, and a space shuttle. If you are ever stuck at Dulles Airport and have some time to kill, there is a very cheap ($0.50 each way per person) shuttle between the airport and the museum.

For those unfamiliar with American aircrafts (as I mostly am), the Enola Gay is the plane that dropped the atomic bomb on Hiroshima. The SR-71 blackbird is the fastest plane ever built, even though it was built in the 70s. It flies so fast that at rest, its joints aren’t perfectly sealed, and it can leak fuel. This is because the metal expands significantly due to heat at high speeds. The museum also hold various antique aircrafts, aircraft oddities, engines and engine cross sections. Another area holds retired military planes, and a third area holds NASA artifacts. I went there a couple of years ago. My creative commons folder of images is here, and I include a few pictures below.

The SR-71 blackbird:

The Enola Gay: