Northwest Africa 5000 (NWA 5000) was originally part of the moon. In order to comprehend the history of this lunar meteorite, we must first understand the origin of our nearest celestial neighbor.

The most accepted theory of how the moon was created is referred to as the "Giant Impact" theory. Most scientists believe the moon was created when a planet-sized body named “Theia” impacted the Earth. This happened during the very early history of the Earth about 4.5 billion years ago. This impacting body was destroyed during the collision, ejecting material from itself as well as Earth, into space. The fragments from this event were trapped by the Earth’s gravity, orbiting in a large array of debris. Through a gravitational process called accretion, the pieces were brought back together to form the moon.

We know from observation and the Apollo missions that there are two main classes of rocks from the moon. The first type is referred to as "mare" (meaning "sea"), pertaining to the darker areas of the moon mainly composed of ancient (3.0 to 3.8 billion year old) basalt lava flows. The second type referred to as "highlands" pertains to the lighter colored areas of the moon mainly composed of feldspar-rich anorthosite rocks. NWA 5000 is a unique highlands-monomict gabbroic breccia (meaning a type of rock mainly made of fragments of gabbro). The moon is believed to be about 4.5 billion years old and for about 600 million years during its early history was bombarded by pieces left over from formation of the planets. Impacts continued to pulverize the surface of the moon at a decreasing rate, creating the heavily cratered surface. During this time, melting of the lunar mantle produced basalt magma that erupted into the larger basins producing the dark areas of the moon, again referred to as "mare". Knowing this history of the moon, we know that NWA 5000 is ancient, making it older than most known Earth rocks.

The next period of NWA 5000’s existence was relatively quiet until a massive impact event occurring around 3.2 billion years ago created a giant melt sheet of a type of rock referred to as gabbro.  The impacting body left exotic 4.5 billion year old material in this Lunaite solving the mystery of why there is metal embedded in gabbro clasts (something that was never observed before NWA 5000 was studied.)  Another asteroid impact around 600 million years ago was mostly responsible for producing its distinctive brecciated matrix as well as bringing this rock to the surface of the moon.  This is where it was exposed to the solar wind, which implanted Helium 3 gas bubbles into the matrix. Then another impact event ejected this rock from the moon and created the interesting glass veins. According to ongoing studies, this happened around 2 thousand years ago.

After floating around in space for millennia, NWA 5000 intercepted the Earth’s orbit and was pulled in by its gravity. At first it was probably the size of a basketball. When it hit the Earth’s atmosphere at cosmic velocity (an estimated 11-30 kilometers per second) the surface began to heat up. As it heated up, it gave off light, making it a meteor (a shooting star). At this point, material began to ablate from its surface and spalled off as a glowing trail of meteoritic material. During this entry phase into the atmosphere it lost about half of its mass, becoming the size of a bowling ball.

Eventually the Earth’s atmosphere, acting as a brake, slowed it down to about 300 kilometers per hour at about 12 – 16 km altitude, arresting the ablation process. Most meteoroids do not survive this part of the trip thus never becoming meteorites. NWA 5000 then dropped to Earth only under the influence of gravity about 1,000 years ago, landing in the sands of the Western Sahara and thus became an exceedingly rare lunar meteorite.

This celestial masterpiece lay undisturbed for eons deep in the world’s largest and hottest desert, the Sahara, until it was liberated by some very fortunate hunters of treasure in July of 2007. The meteorite was provided to the famous Hupé Collection after lengthy negotiations. The Hupé Collection is known for possessing the world’s most complete and notable assemblage of planetary main masses.

A team of world renowned scientists, photographers, artists and consultants was assembled and sworn to secrecy for months due to security concerns.  The meteorite was then quietly studied at the University of Washington where it was given the informal name “The Rock” because its immense posture commanded more than just the next number in a sequence.  There was no mistaking what rock was being referred to in the laboratories when using this moniker.  Scientists were permitted to select their own type specimen, and a repository amount of 40 grams was committed in advance of the honorific official name Northwest Africa 5000 being assigned.  Washington University in St. Louis and Carnegie Institution in Washington D.C. soon provided additional confirmation of its lunar provenance by way of bulk elemental analysis and oxygen isotope testing.  Several more laboratories including Berkeley Geochronology Center, Berkeley Space Sciences Laboratory, Purdue University, ETH-Zurich, University of Arizona, Lawrence Livermore National Laboratory, and National High Magnetic Field Laboratory at Florida State University have helped to translate the extraterrestrial history of this exceeding rare meteorite from the Moon.

Preparation posed its own set of challenges.  It is understandable how nervous a diamond cutter must feel when confronted with the task of cutting the big one.  Even though in the past, we have prepared well over 25,000 meteorite slices, the entire team lost sleep over this one, having never cut something this valuable before.  Only after studying a very accurate casting for weeks and crunching the numbers was our group able to put together a cutting plan.  This would require a flawless execution since the tolerances were within a few millimeters of reaching our preset limits. After careful consideration, a more rigid, precision diamond lapidary saw was chosen to perform the main cuts even though cutting loses would be great.  The freshly balanced, calibrated and sterile saw performed flawlessly, leaving no tell-tale cutting marks on the main mass.  The flat surface (referred to as a window) was then lightly polished by hand using diamond grit.  Most would agree that the end product is the best in the universe

Some may ask “Why all of the fuss, aren’t we just talking about a rock?”  Our answer is simple, “A diamond is also just a rock but nowhere near as rare, complex or scientifically important as a rock from our nearest celestial neighbor, the Moon.”  If this rock were brought back from the Moon by astronauts, its proportionate cost would be enormous, much more than that of flawless diamonds.  On the other hand, natural processes brought this rock from the Moon here to Earth.  An asteroid strike on the Moon caused the ejection of this meteorite into an Earth-crossing orbit, which is a much less expensive yet time consuming process.  

This meteorite made its public debut at the Royal Ontario Museum from December 20^th 2008 to April 15^th 2009.  This is the largest lunar meteorite ever to be placed on public display.  It was prominently exhibited in its own 11 by 8 by 2 feet display at the very front and center for the grand opening of the new Teck Suite of Galleries: Earth’s Treasures.  It was intensely popular as patrons viewed it both on the way in and once again upon exiting.