Sea silk is an extremely rarefabric that is made from the long silky filaments, orbyssus, secreted by a gland in the foot ofpen shells (in particularPinna nobilis).[1] The byssus is used by the mussel to attach itself to the sea bed.[2] It was previously produced inSardinia andTaranto until the early 20th century and is still made at small scale by a few people in Sardinia.[3]
The cloth produced from byssus is extremely light and warm. It is also often described as being very thin, although it is similar in thickness to other fibers such assilk.[4] Byssus was said to be so fine that a pair of women's gloves made from the fabric could fit into half awalnut shell and a pair of stockings in asnuffbox.[5] However,Helen Scales has put forward the idea that this idea actually refers toLimerick gloves made from a finekid leather that were sold inside walnut shells as a marketing stunt, and over time, the walnut packaging and beliefs about byssus cloth were conflated.[6]
Pinna nobilis produces a beard of about 1,000 fibers to attach itself to the sea floor, which are all attached to a central stem. They can be up to 20 centimetres (7.9 in) long.[3]
The removed beard is processed in several steps. First, it is rinsed in the sea to remove debris. It is then washed in fresh water and manually cleaned.[7] This may be followed by a third bath, again in fresh water.[8] After drying, it iscarded and thenspun by hand.[7] Beginning in the early 19th century, the beards were sometimes left intact after being cleaned and combed and then sewn together in a close, overlapping manner to produce an effect resembling fur.[8]
The fibers vary in color and have a unique egg-shaped profile when viewed under a microscope.[3][8] They are 10–50 microns in diameter, which is comparible to other natural fibers such as silk (11–15 microns), merino wool (18–25 microns) ormohair (20–40 microns).[4] It is not very strong, especially when wet, compared to other fibers.[9]
Bysus can be soaked in lemon juice for a few hours to produce a golden color.[7] There are no known historical examples of dyed sea silk, probably because the natural color was highly valued. Modern experiments with dyeing sea silk have not shown dramatic color changes.[8]
While a few extant woven objects are known, most were knit, and many are gloves.[8] A knitted pair of gloves probably took the byssus from around 150 shells to produce.[3] There are historical reports of sea silk being mixed withsilk, probably for economic reasons, and also with wool, though very few objects with mixed fibers are now known to exist. Sea silk fibers may also be used for embroidery.[8]
Tracing the history of sea silk is difficult in part because the wordbyssus originally referred to fine fabric made of linen or perhaps cotton, and in theMiddle Ages, also to that made of silk.[10] The first written mentions of sea silk date to the 2nd century AD, and the oldest piece of sea silk that has been found dated to the 4th century AD; a fragment was discovered in a grave inBudapest in the remains ofAquincum. However, the fragment was lost duringWorld War II.[3][11] The oldest surviving sea silk object is a knit hat from the 14th century, which was found in a waste pit nearParis.[12]
The Greek text of the (196 BC)Rosetta Stone records thatPtolemy V reduced taxes on priests, including one paid inbyssus cloth. This is thought to be finelinen cloth, not sea silk. InAncient Egyptian burial customs,byssus was used to wrapmummies; this was also linen and not sea silk.[10]
Thesophist authorAlciphron first records "sea wool" in his (c. 2nd century AD) "Galenus to Cryton" letter.[13]
Sea silk has been suggested as an interpretation of the nature of theGolden Fleece that was sought byJason and the Argonauts[14] but scholars reject this hypothesis.[15]
The early ChristianTertullian (c. 160–220 AD) mentions it when justifying his wearing apallium instead of atoga:
Nor was it enough to comb and to sew the materials for a tunic. It was necessary also to fish for one's dress; for fleeces are obtained from the sea where shells of extraordinary size are furnished with tufts of mossy hair.[16]
Several sources mentionlana pinna ("pinna wool"). EmperorDiocletian's (301 AD)Edict on Maximum Prices lists it as a valuable textile.[17]
The Byzantine historianProcopius's c. 550 ADPersian War, "stated that the five hereditarysatraps (governors) of Armenia who received their insignia from the Roman Emperor were givenchlamys (or cloaks) made fromlana pinna. Apparently only the ruling classes were allowed to wear these chlamys."[18]
TheArabic name for "sea silk" isṣūf al-baḥr ("sea wool"). The 9th-century Persian geographerEstakhri notes that a sea-wool robe cost more than 1000 gold pieces and records its mythic source:
At a certain period of the year an animal is seen running out of the sea and rubbing itself against certain stones of the littoral, whereupon it deposes a kind of wool of silken hue and golden colour. This wool is very rare and highly esteemed, and nothing of it is allowed to waste.[19]
Two 13th-century authors,Ibn al-Baitar andZakariya al-Qazwini, repeat this inaccurate "sea wool" story.[20]
The city ofTinnis on theNile Delta was known for its garments made of sea silk, calledbuqalamun fromhypokalamon, the Greek name of thebyssus mollusc.[21]
Beginning in theEastern Han dynasty (25–220 AD), Chinese histories document importing sea silk.Chinese language names include "cloth from the west of the sea" and "silk knitted by mermaids".[22][23]
The 3rd century ADWeilüe or "Brief Account of the Wei", which was an unofficial history of theCao Wei empire (220–265 AD), recordshaixi ("West of the Sea") cloth made fromshuiyang ("water sheep"):[24]
They have fine brocaded cloth that is said to be made from the down of "water-sheep". It is calledHaixi ("Egyptian") cloth. This country produces the six domestic animals [traditionally: horses, cattle, sheep, chickens, dogs and pigs], which are all said to come from the water. It is said that they not only use sheep's wool, but also bark from trees, or the silk from wild silkworms, to make brocade, mats, pile rugs, woven cloth and curtains, all of them of good quality, and with brighter colours than those made in the countries of Haidong (East of the Sea).[25]
The c. 5th century ADHou Hanshu ("Book of the Eastern Han") expresses doubt about "water sheep" in the "Products ofDaqin" section. "They also have a fine cloth which some people say is made from the down of 'water sheep,' but which is made, in fact, from the cocoons ofwild silkworms".[26] The historianFan Ye (398–445 AD), author of theHou Hanshu, notes this section's information comes from the report that GeneralBan Yong (son of GeneralBan Chao, 32–102 AD) presented to the Emperor in 125. Both Bans administered theWestern Regions on theSilk Road. Hill considered it likely that the original reports correctly referred to sea silk, and later cloth that was examined in China was made of the similar-lookingwild silk, leading to earlier reports being dismissed.[27]
The (945 AD)Tang shu "Book of Tang" mentionedHaixi cloth from Folin (Byzantine Syria), whichEmil Bretschneider first identified as sea silk from Greece. "There is also a stuff woven from the hair of sea-sheep, and calledhai si pu (stuff from the western sea)". He notes, "This is, perhaps, theByssus, a clothstuff woven up to the present time by the Mediterranean coast, especially in Southern Italy, from the thread-like excrescences of several sea-shells, (especiallyPinna nobilis)."[28]
The early 6th century ADShuyiji ("Records of Strange Things") mentions silk woven byJiaoren, "jiao-dragon people", whichEdward H. Schafer identifies as sea silk:
In the midst of the South Sea are the houses of thekău people who dwell in the water like fish, but have not given up weaving at the loom. Their eyes have the power to weep, but what they bring forth is pearls.[29]
This aquatic type of raw silk was calledjiaoxiao, with the first character meaning "shark" and the second a form of raw silk, although it was also described in some sources as a high-qualitymuslin orchiffon.[23]
ArchbishopGiuseppe Capecelatro [it] gave dignitaries gifts made of sea silk in the 1780s, hoping to encourage demand to help provide for sea silk producers in need of work. Sea silk objects began to be put on display internationally in the 19th century; it was shown at theLouvre in 1801 and at theCentennial Exposition in 1876.[3]
Sea silk was also mentioned in 19th century fiction.Alexander Serov's 1863 operaJudith includes an aria "I shall don my robe of byssus" (Russian:Я оденусь в виссон).[30] InJules Verne's 1870 novelTwenty Thousand Leagues Under the Seas, the crew of theNautilus wear clothes made of byssus (alternately translated as "seashell tissue" or "fan-mussel fabric").[31]
The sea silk industry inTaranto grew somewhat beginning in the 1920s with the advent of a private school run by Rita del Bene; however, it disappeared there with the onset ofWorld War II and did not return after the war.[3] Also in the 1920s, Italo Diana began a school on the island ofSant'Antioco nearSardinia.[7]
Pinna nobilis has become threatened with extinction, due to overfishing, the decline inseagrass fields, and pollution. Since 2016, populations have also been attacked by a parasite calledHaplosporidium pinnae, which has caused mass die-offs.[32] As it has declined so dramatically, the sea silk industry has almost disappeared, and byssus is difficult to come by; since 1992, it is illegal to harm or harvest livingPinna nobilis. The art is now preserved only by a few women in Sant'Antioco.[3]
"Project Sea-Silk" from theNatural History Museum of Basel, run by Felicitas Maeder, has been collecting extensive data and studies on the subject since 1997.[33][7]
Chiara Vigo [gl] has claimed in various media to be the sole person living today to master the art of working with byssus, and she runs the Sea Silk Museum in Sant'Antioco.[34][35] Maeder has accused Vigo of creating a false historical narrative about sea silk.[36] Vigo says she has a method to harvest bysus without harming the shells by trimming 10 centimetres (3.9 in) from the beard, although Scales expressed skepticism that this would produce the amount of byssus Vigo says she takes (600 grams (21 oz) per year; the intact beards of fifty shells produce 30 grams).[3]
A few other women also still produce and work with byssus in Sant'Antioco, such as the sisters Assuntina and Giuseppina Pes, who were taught the art by Efisia Murroni. Murroni, who was a pupil of Diana, died in 2013 aged 100.[3][36] The sisters use vintage byssus that has been donated to them,[32] and the byssus ofAtrina pectinata, a shell in the same family, has been used by Arianna Pintus in her workshop inTratalias as a substitute forPinna nobilis.[7]
