Why are diamonds, mica, quartz, and beryllium critical to national defense?

Apparently the US has huge stockpiles of various materials. They were saved up during the Cold War “just in case.” Now they’re getting sold off, save for some materials such as those mentioned in the quote. What are they used for and why are they critical to national defense?

Diamonds are critical for industrial cutting applications (diamond-tipped drills). Beryllium is prized for its high strength-to-weight ratio in aerospace applications, where every extra ounce of payload costs more to lift into orbit, and reduces the efficiency of on-orbit engines.

I don’t know what the other two are used for.

Quartz is used in the manufacture of PiezoElectric Quartz Crystal Units, a once critical industry in the USA. An industry which has been, for the most part, ceded to the Far East. Crystal Units, or simply crystals, are used as frequency control and/or timing devices; quartz crystals are the best means yet discovered for these applications. During WW II, the Manhattan Project carried the highest priorities; quartz crystal units were second.* Natural quartz stones, most of which came from Brasil, were stockpiled for future use; good quality natural stones were hard to come by. Natural quartz has now been supplanted by man made quartz.

*No cite; info was obtained from one of the founding fathers of the crystal industry in the US.

Quartz lenses, unlike glass lenses, are transparent to ultraviolet, so there are photographic intelligence reasons as well.

Don’t beryllium and quartz have applications in the manufacturing of lasers?

1920’s style death rays…

Inertia is probably a factor. I suspect mohair, horse bridles, and vacuum tubes are still stockpiled somewhere. Certain minerals and metals are, or were, only available in countries who are on less than friendly terms with the US.

Beryllium is also used in nuclear weapons and nuclear reactors, as it reflects neutrons.

Mica is used to manufacture high-frequency capacitors, important in communications systems.

Quarts is used to manufacture high-frequency oscillators, which are used in basically every computing device ever made.

Sheet mica was once quite important as an insulating component in radio frequency capacitors. Block and powdered mica are still used as insulators for steam systems. There are a host of other uses for the stuff, but the strategic stockpile is being reduced as other materials gain popularity as substitutes for the mineral.

Other people have listed uses for quartz, mica, and diamonds (there are still some that could be added, but they’re not that interesting) so I’ll make a few notes about beryllium, which due to its high strength, thermal conductivity, low neutron absorption cross section, fatigue resistance, et cetera, is used extensively in aerospace structures, nuclear reactors and weapons, high temperature and exotic alloys, and electronics. Next to tungsten (or perhaps in front of it) it is probably one of the most important “exotic” (i.e. discovered in the Common Era) elements in modern technological infrastructure.


I think it’s like all government handouts, each pol tries to get his local industry in on the pork. His vote to fund the program in return for local minerals being included, no matter how tenuous the tie to real defense needs.

Beryllium is also ground up and mixed with Am-241 where it becomes a neutron source which can be used to assist the initiation of a nuclear bomb. Probably not used much these days what with pulsed neutron generators being available, but you still don’t want the stuff out and about if you could help it.

Beryllium is also hazardous to your health, or rather, can be if you have the right genetic make up. The problem is, you don’t know if you have the right genetic make up until it’s too late.

During WWII because of national security reasons, people working with beryllium weren’t told what the material was, many of them have developed health problems similar to asbestos exposure later on in life. Copper beryllium is said to be particularly nasty stuff in that regard.

Large sheets of mica are also used in optical devices like Kerr cells, that are used in pulsed high-energy laser systems. Nothing quite like large sheets of mica work as well, and I don’t think they can grow mica artificially. I can see that being stockpiled.

Quartz, though – that puzzles me. Quartz is one of the most common minerals there is. It makes as much sense to stockpile sand – which is quartz.

Beryllium copper was used in the oil and gas industry where non meganetic materials were needed. It is easier to handle and machine than monel or P500 series cro mo non mag alloys and is a little softer. BeCu is fine to handle as a solid lump but one has to be careful when grinding or machining that may generate a fine dust. Brush Wellman were the key manufacturer of this stuff and still make a lot of various components out of it.

As you say, it does cause all manner of lung nasties, but only when ground up. Dust from the nickle, cobalt and copper used in the alloying is not that healthy either.


That is true, as far as it goes. Quartz (SiO2) is probably the most common mineral there is; it makes up a large percentage of the earth’s crust, but I’ve forgotten the exact number. However, the key to its value lies in the fact that quartz is a piezoelectric material and it is the exploitation of the piezoelectric property that allows its use as a frequency control device. While there are many other piezoelectric materials, quartz stands alone in having other neccesary attributes that make it ideally suited for the manufacture of frequency control devices. Grains of sand may or may not be piezoelectric and are much too small for manufacturing purposes. In addition to that, the slices of quartz which are used in manufacturing frequency control devices must be carefully aligned in relation to the original crystalographic axes. X-ray diffraction is used for the purpose and it isn’t a simple task. We must also keep in mind that all quartz is not piezoelectric; if it is heated to, IIRC, 575 degrees C, the piezoelectric properties are lost. At one time, the manufacture of frequency control devices was considered an industry that was critical to America’s defense. The Armed Forces maintained a Qualified Producers List (QPL). Having one’s company on that list was evidence enough that one knew what one was doing; the testing required was very difficult to pass. At that time, only natural quartz was certified for use and stones large enough to be processed were found nearly exclusively in Brazil. During WWII, German submarines patrolled the coast of Brazil specifically targeting ships carrying quartz stones to the USA. It was for that reason that aircraft were assigned the task, meaning that quartz was a critical material that carried a very high priority. The development of man-made or cultured quartz was also a very high priority; today cultured quartz has supplanted natural quartz as the favored material. I could go on and on and I guess I already have. There are numerous articles concerning quartz, piezoelectricity, and frequency control available on the internet—a few of them were written by me, not that I’m bragging or anything. I designed and manufactured frequency control devices for many years and I will be forever bitter that my beloved industry has been ceded to off shore sources.

Is Sam Donalson (Bad hair guy0 still getting a government subsidy for his angora goat ranch in Texas? In this era of synthetic fabrics, why is angora hair still “strategic”?

Well, duh!

If we have to fight the Gorn in a deathmatch arranged by superintelligent aliens, we can make a crude but effective firearm. (Assuming that there’s sulfur, charcoal, saltpetre and a length of bamboo handy as well).

“300 quatloos for the new comers!”