The Randalínur socks are part of the book Socks of Iceland which is released in the form of a Club: get a pattern every Thursday until the end of the year 2020. You can join at anytime.
For more info, please visit https://icelandicknitter.com/product/socks-of-iceland-club/

The Fríður socks are inspired by a pair of Icelandic socks in the National Museum in Copenhagen, Denmark. They were knitted with a fine natural brown wool yarn and reached under the knee. They had a ribbed folded cuff, a band heel and a star toe and were shaped with increases and decreases on both sides of a line of purl stitches at the back of the leg. They were widest around the calf.
The socks are part of a knitted man costume that was given to the Museum in 1858 and that has been thoroughly researched by professor associate Fríður Ólafsdóttir in her book about Icelandic men clothes 1740-1850. The socks are probably newer than the costume itself, the original socks having been destroyed with use. It is possible to date socks from the sock forms, made of wood or paper that are stored in the museums. From the shape of the socks in the Danish Museum, Fríður thinks it is likely that they are from the first half of the 19th century.
I retained all the main characteristics in my design but replaced the line of purl stitches at the back of the leg by a line of openwork. A few short rows under the foot make the sole slightly longer and the socks more comfortable, a technique seen in other old socks. Rather than a folded edge at the top, a band of stranded knitting just under the ribbing is mimicking the woven sock band that would be tight under the knee. Those bands were often tablet woven, decorated with all sorts of colorful motifs with the initials of their owner. The old Icelandic alphabet chart provided will allow you to customize the socks with your own initials or the person the socks are intended for. This alphabet comes from an old sjónabók, an Icelandic pattern manuscript dating from the 17th century.

Sizes: 1(2,3,4) to fit foot 21(23.5,24.5,27) cm / 8¼ (9¼,10,11)” in circumference.
You can achieve more sizes by changing needle size and adjust the length by adding or withdrawing rnds.
You can also adapt the calf circumference by adding/withdrawing increases at the back of the leg, and adding/withdrawing decreases accordingly. The stranded band can also be altered by adding more or less repeats to the central front motif.
Socks shown are a size 2.

Finished measurements:
Foot circumference: 18.5(21,23,25.5) cm / 7¼ (8¼,9,10)”
Foot length: 18(20,22.5,25) cm / 7(8,9,10)”
Calf circumference: 28.5(31,33,35.5) cm / 11¼(12,13,14)”
Sock height (adaptable) from cuff to ankle bone: approx. 33(33,35,38) cm / 13(13,13¾,15)”

Recommended fit: negative ease of 2.5 cm /1” in circumference and 15% in length

Yarn: Katla sokkaband by Hélène Magnússon: pure new Icelandic lambswool with a dash of silk (1%), DK/sport weight sock yarn, 4 ply, non superwash, 100g skein = 220 m / 240 yds: 2(2,2,2,3) skeins MC; leftovers for the CCs.

Yardage used:
MC Raven black: 300(340,400,475) m / 324(370,437,518) yds
CC1 Palagonite ochre 12(14,16,19) m / 13(15,17,21) yds
CC2 Arctic coral 4(5,6,7) m / 4(5,6,7) yds
CC3 Natural grey 12(14,16,19) m / 13(15,17,21) yds