Constantin Fahlberg, a young chemist, sat down to dinner in Baltimore one evening in June 1878 and found the crust of a roll remarkably sweet when he bit into it. He had spent the day oxidizing toluenesulfonamide in Ira Remsen's lab at Johns Hopkins, and some of what he made was still on his hands. He ran back to the lab and tasted everything on his worktable until he found the compound he named saccharin, the first commercial artificial sweetener. Years later Fahlberg patented saccharin without telling his old professor Remsen or including Remsen's name on the patents. He built the world's first saccharin factory in Germany. Toluenesulfonamide is still the starting material for industrial saccharin, and it also makes printing inks more flexible and goes into the resin that gives nail polish its gloss. The US imports about 1.7 million pounds of toluenesulfonamide a year and reports no production of its own.

A jasmine-lily scent ingredient in perfume sells for $464 per gram, 5 times the price of gold. This molecule gives fragrance formulas a green floral scent that reads as jasmine, lily, and lemon. Perfumers buy the purified material when they need the same scent to survive batching, storage, and blending. AA BLOCKS in the US sells 500 milligrams for $232. Sigma-Aldrich in China lists 500 milligrams for $176. This is one of 838 molecules selling today for more than gold per gram. Here's the list:

A raw ingredient in cancer treatment capsules sells for $1,248 per gram, 13 times the price of gold. Larotrectinib sulfate blocks TRK, a growth signal some tumors use to keep growing. When a cancer depends on that signal, the molecule can slow the tumor by cutting off the message. That makes the purified ingredient valuable to researchers and drug manufacturers. Molnova in China lists larotrectinib sulfate at $624 for 500 milligrams. GlpBio in Montclair, CA, US, sells 50 milligrams for $197.00. This is one of 838 molecules selling today for more than gold per gram. Here's the list:

In 1967 Nissim Calderon, a chemist at Goodyear's rubber lab in Akron, Ohio, mixed dark blue crystals of tungsten hexachloride with an aluminum compound and pentene and found the pentene's double bonds breaking open and trading halves. No known reaction explained these products; Calderon named the exchange olefin metathesis. Chemists won the 2005 Nobel Prize in Chemistry for explaining how the reaction happens, and now use it to make drugs and plastics they previously lacked a way to make. Chipmakers use tungsten hexachloride to deposit tungsten films inside memory chips, in place of a fluorine compound whose byproduct etches away the chip's insulation. The US imports about 35,000 pounds of it a year and makes none.

The dye that makes black denim black can also weaken the cotton it colors. Sulfur Black 1 leaves traces of free sulfur in the cloth, and in humid storage a sulfur acid forms and attacks the fiber before anyone wears it. Dyers call the defect tendering and prevent it with an aftertreatment. Mills use the dye anyway because sulfur dyes are cheap and wash well, and they color more cotton than any other class of dye. When the British blockade cut off German dyes in 1915, sulfur black was the one dye mills outside Germany could make in quantity and at steady quality, and American textile firms built a fashion campaign on it, urging a national vogue for black and white. A plant outside Charlotte, North Carolina made sulfur dyes from 1936. Its owner petitioned Washington in 1992 over dumped imports, and investigators agreed the dyes were selling below fair value but found no injury to the industry. The plant stopped making dye in 2005, and in 2019 the only company that reported Sulfur Black 1 to the EPA imported all 390,000 pounds of it.

A chemical used to keep flexible plastic and rubber soft sells for $217.80 per gram, 2.3 times the price of gold. Dihexyl hexanedioate is a plasticizer, which means it works like a spacer inside plastic and rubber. It helps the material bend without cracking, so manufacturers can turn hard ingredients into soft parts. That softness matters when raw plastic becomes flexible finished material. Labotest KG in Germany sells 5 grams for $1,089. Aaron Chemicals LLC in Hong Kong sells 1 gram for $327. This is one of 920 molecules selling today for more than gold per gram. Here's the list:

Four elements on the periodic table are named after a single feldspar quarry on an island outside Stockholm. The pit at Ytterby yielded an odd black rock in 1787, and chemists spent the next century boiling new metals out of it: yttrium, terbium, erbium, and in 1878 a white powder that Jean de Marignac in Geneva called ytterbia. We know it as ytterbium oxide. For about a hundred years the powder stayed a laboratory curiosity. Then fiber-laser engineers found that silica glass doped with ytterbium converts diode light into a beam strong enough to cut steel, and ytterbium became the standard dopant in the high-power lasers that cut and weld metal on factory floors today. The US imports around 16,000 pounds of ytterbium oxide a year and makes none of it.

A lavender fragrance alcohol sells for $478 per gram, 5 times the price of gold. It helps give lavender oil its fresh floral smell. Fragrance makers buy the purified version to keep lavender, citrus, and herb notes consistent when plant oils vary by harvest. J&W Pharmlab, LLC in the United States lists 5 grams at $2,390. AK Scientific, Inc. in the United States lists 1 gram at $598. This is one of 838 molecules selling today for more than gold per gram. Here's the list:

Daniel Barringer spent 26 years and most of his fortune drilling Meteor Crater in Arizona, convinced a giant iron meteorite lay buried under the floor. The impact had vaporized most of the meteorite, so nothing was left to find, and he died in 1929 with the shafts empty. Mineralogists honored him anyway, and in 1969, picking through a pallasite meteorite, they found a new mineral and named it barringerite, iron phosphide (Fe2P) with a share of the iron replaced by nickel. On Earth the same compound comes out of factories. Battery makers meet it in production, because Fe2P forms inside lithium iron phosphate cathodes, where a thin conductive layer of it helps a poorly conducting material move electrons. Those cells go into electric cars and grid storage. Last year the US imported about 88,000 pounds of iron phosphide and reported producing none.

A coating ingredient used in paints and adhesives sells for $217.80 per gram, 2.3 times the price of gold. 3,3,5-Trimethylcyclohexyl methacrylate is a reactive monomer. It links into polymer chains as paints, coatings, and adhesives harden, helping the finished film stick and resist wear. Manufacturers buy purified samples to test formulas before scale-up. Labotest KG in Germany lists 5,000 milligrams for $1,089. Aaron Chemicals LLC in Hong Kong lists 1 gram for $488. This is one of 838 molecules selling today for more than gold per gram. Here's the list: