subject says it all.
I will get it started and say absolutely. Perfect pearls used to be extremely rare before modern farming practices started. Diamonds OTOH were not one of the most cherished gemstones until DeBeers got ahold of the situation in the middle 1900’s and that remains to this day (if you want an honest to God conspiracy story packed with blood, guts, and slavery, DeBeers is the company you are looking for). I have read about people spending the equivalent of several million dollars on a pearl necklace before the bottom dropped out. In the meantime, DeBeers invented the story of the traditional diamond ring or necklace to those in love. They have a near monopoly on the supply to this day. Diamonds aren’t especially rare and several entities are trying to brake it up including technology that can manufacturer 100% legitimate diamonds of any quality in the lab.
None of this is embellished and Cecil did an article on it.
You’ve also got to consider that pearls are, by a huge margin, the rarest gemstones known in the Universe. Amber is probably second, and anything else is so far behind as to not be worth mentioning.
Diamonds aren’t uncommon. Diamonds are mined by the bucketful daily — 26,000 kg per year, says Wikipedia, or 57,300 pounds. For scale, that’s about the weight of a Sherman tank.
What you meant to ask about was gem-quality diamonds, which consitute only about 20% of the diamonds mined.
From here, note the price of this pearl:
That’s about $1,600,000 per ounce.
Compare to the Hope Diamond, weighing in at 45.52 carats, which sold for a variety of prices in and around the same time:
Even on the low-ball $80K figure, that’s $3,840,000 million per ounce.
True, this compares one exceptional but unnamed pearl with one of the more famous and notorious diamonds of the era. A more apt comparison, which I will leave to somebody else, is a typical pearl versus a typical (ie, industrial) diamond.
Whoa, really? I find this amazing. I’d never heard this. Is there someplace I can read more about this kind of thing (relative rarity of gems)?
I’m a little confused… The article said the pearl sold for 25K, and was just under 1/4 ounce. By my math that makes it worth slightly more than 100K per ounce.
Did you really mean $3,840,000,000,000,000 or just $3.84 million? 1 ounce = 141.7 carats, so at 80,000 for a 45 carat diamond, it’s about 25,000 per ounce.
I think that this just logically follows from the fact that as a ‘gem,’ pearls (and amber) are created from biological materials which are probably unique to planet Earth. Other gems are likely to be found elsewhere in the universe; pearls not so much.
Who would think flowers could be used as currency and traded like stock? Tulips in the 1600’s were exceedingly high priced and a coveted luxury itme and a status symbol. Needless to say that bubble burst.
I’m not sure I follow. A few posts up mention is made of the fact that pearls are farmed pretty routinely.
Yes, but only on one planet in the entire universe. Diamonds, on the other hand, are formed by geological process that are probably common throughout the universe.
Note “Universe”. Lots of other placs to find diamonds, but only earth has amber (fossilized tree sap) and pearls.
Onna-otha-hand, we’re not going to be acquiring any extraterrestrial mineral gems any time soon, right? For all practical purposes, isn’t the earth currently the only known source of all types of prized gems?
(Or have we had any diamonds or other nice crystals showing up in meteorites, say? I suppose it’s possible but off the top of my naive head, it doesn’t sound likely…)
Oops. I meant per pound on both, not per ounce. Heh. 
I’m not aware that Amber is a gemstone. I’d rather assumed that it isn’t a stone or a gem at all. With the breakdown of the Soviet Union a few years back, amber has flooded into the West and is worth bupkis at this point. You can buy amber necklaces wholesale so cheaply, you just can’t believe it.
The universe is a pretty big place. Although I get the point, I sure wouldn’t want to bet my life savings on it.
One other thing about diamonds is that until faceting was invented, they weren’t all that impressive. Ancients did value diamonds and admire them for their hardness, but they were not regarded as the ultimate gem as many do today. The favored status of diamonds, presumably as a result of DeBeers’ efforts, is so evident that even the terminology of the field is influenced by it: Unless things have changed, the very word “gemstone” refers not to diamonds, but to everything else. Diamonds are their own category.
Despite all this, pearls above a certain size are still astonishingly expensive, as this site clearly shows. While a big part of the cost in finished pearl jewelry is the matching of size and color, as for earrings and, especially, necklaces of uniform size, I’m still stunned by these prices.
Until we discover the Planet Of The Oysters!
I don’t know if there’s any “official” definition of “gemstone”, but Wiki sez: