Spermaceti is a wax

Wax

thumb|right|[[Cetyl palmitate]], a typical wax ester.Wax refers to a class of chemical compounds that are plastic near ambient temperatures. Characteristically, they melt above 45 °C to give a low viscosity liquid. Waxes are insoluble in water but soluble in organic, nonpolar solvents...

 present in the head cavities of the sperm whale

Sperm Whale

The sperm whale, Physeter macrocephalus, is a marine mammal species, order Cetacea, a toothed whale having the largest brain of any animal. The name comes from the milky-white waxy substance, spermaceti, found in the animal's head. The sperm whale is the only living member of genus Physeter...

 (Physeter macrocephalus). Originally mistaken for the whales' sperm

Sperm

The term sperm is derived from the Greek word sperma and refers to the male reproductive cells. In the types of sexual reproduction known as anisogamy and oogamy, there is a marked difference in the size of the gametes with the smaller one being termed the "male" or sperm cell...

 (hence the name), spermaceti is created in the spermaceti organ inside the whale's head and connected to its nasal passage. Its biological function is uncertain.

Spermaceti is extracted from sperm oil

Whale oil

Whale oil is the oil obtained from the blubber of various species of whales, particularly the three species of right whale and the bowhead whale prior to the modern era, as well as several other species of baleen whale...

 by crystallisation at 6 °C, when treated by pressure and a chemical solution of caustic alkali

Alkali

In chemistry, an alkali is a basic, ionic salt of an alkali metal or alkaline earth metal element. Some authors also define an alkali as a base that dissolves in water. A solution of a soluble base has a pH greater than 7. The adjective alkaline is commonly used in English as a synonym for base,...

. Spermaceti forms brilliant white crystals that are hard but oily to the touch, and are devoid of taste or smell, making it very useful as an ingredient in cosmetics, leatherworking, and lubricants. The substance was also used in making candle

Candle

A candle is a solid block or cylinder of wax with an embedded wick, which is lit to provide light, and sometimes heat.Today, most candles are made from paraffin. Candles can also be made from beeswax, soy, other plant waxes, and tallow...

s of a standard photometric

Photometry (optics)

Photometry is the science of the measurement of light, in terms of its perceived brightness to the human eye. It is distinct from radiometry, which is the science of measurement of radiant energy in terms of absolute power; rather, in photometry, the radiant power at each wavelength is weighted by...

 value, in the dressing of fabrics, and as a pharmaceutical excipient

Excipient

An excipient is generally a pharmacologically inactive substance used as a carrier for the active ingredients of a medication. In many cases, an "active" substance may not be easily administered and absorbed by the human body; in such cases the substance in question may be dissolved into or...

, especially in cerate

Cerate

Cerate, historically simple cerate, is an unctuous preparation for external application, of a consistency intermediate between that of an ointment and a plaster...

s and ointments.

Properties

Spermaceti is insoluble in water, very slightly soluble in cold alcohol

Ethanol

Ethanol, also called ethyl alcohol, pure alcohol, grain alcohol, or drinking alcohol, is a volatile, flammable, colorless liquid. It is a psychoactive drug and one of the oldest recreational drugs. Best known as the type of alcohol found in alcoholic beverages, it is also used in thermometers, as a...

, but easily dissolved in ether

Diethyl ether

Diethyl ether, also known as ethyl ether, simply ether, or ethoxyethane, is an organic compound in the ether class with the formula . It is a colorless, highly volatile flammable liquid with a characteristic odor...

, chloroform

Chloroform

Chloroform is an organic compound with formula CHCl3. It is one of the four chloromethanes. The colorless, sweet-smelling, dense liquid is a trihalomethane, and is considered somewhat hazardous...

, carbon disulfide

Carbon disulfide

Carbon disulfide is a colorless volatile liquid with the formula CS2. The compound is used frequently as a building block in organic chemistry as well as an industrial and chemical non-polar solvent...

, and boiling alcohol

Ethanol

Ethanol, also called ethyl alcohol, pure alcohol, grain alcohol, or drinking alcohol, is a volatile, flammable, colorless liquid. It is a psychoactive drug and one of the oldest recreational drugs. Best known as the type of alcohol found in alcoholic beverages, it is also used in thermometers, as a...

. Spermaceti consists principally of cetyl palmitate (the ester

Ester

Esters are chemical compounds derived by reacting an oxoacid with a hydroxyl compound such as an alcohol or phenol. Esters are usually derived from an inorganic acid or organic acid in which at least one -OH group is replaced by an -O-alkyl group, and most commonly from carboxylic acids and...

 of cetyl alcohol

Cetyl alcohol

Cetyl alcohol, also known as 1-hexadecanol and palmityl alcohol, is a fatty alcohol with the chemical formula CH315OH. At room temperature, cetyl alcohol takes the form of a waxy white solid or flakes....

 and palmitic acid

Palmitic acid

Palmitic acid, or hexadecanoic acid in IUPAC nomenclature, is one of the most common saturated fatty acids found in animals and plants. Its molecular formula is CH314CO2H. As its name indicates, it is a major component of the oil from palm trees . Palmitate is a term for the salts and esters of...

), C₁₅H₃₁COO-C₁₆H₃₃.

A botanical alternative to spermaceti is a derivative of jojoba oil, jojoba ester

Jojoba ester

Jojoba esters are the hydrogenation or interesterification product of Jojoba oil. Interesterified Jojoba Esters are commonly used in cosmetic formulations as an emollient, due to its remarkable similarity to the natural oils produced by the human skin, and its high oxidative stability...

s, C₁₉H₄₁COO-C₂₀H₄₁, a solid wax which is chemically and physically very similar to spermaceti and may be used in many of the same applications. Esters of cetyl alcohol and jojoba oil are used as a substitute for spermaceti.

Spermaceti processing

Spermaceti was gathered during whaling and was considered a valuable resource by whalers

Whaling

Whaling is the hunting of whales mainly for meat and oil. Its earliest forms date to at least 3000 BC. Various coastal communities have long histories of sustenance whaling and harvesting beached whales...

due to the high price that could be fetched for it. The sperm whale's head was either brought on deck or lashed to the side of the ship where the whalemen would cut a hole in the case. The spermaceti could then be drawn out by bucket or a whaleman would enter the hole and manually remove the fluid. Accounts suggest that this procedure changed little from the earliest days of sperm whaling to the advent of modern technology in the 20th century. Once gathered the spermaceti would be placed in barrels for the voyage home. A large whale could have as much as 500 gallons.

Biological function

Currently there is no agreement on what biological purpose spermaceti serves. There are however hypotheses on its function. It might be used as a means of altering the whale's buoyancy, since the density of the spermaceti alters with its phase. There is a hypothesis that it is used to focus sound waves to stun its prey. Another hypothesis is that it is used as a cushion to protect the sperm whale's delicate snout while diving.