Sunday, February 28, 2010

Super Numbers

This owes much to the wondeful book The Suit by Nicholas Antongiavanni, better known as Manton..

A subject that causes much confusion among many, customers and staff alike, is the subject of super numbers and their correlation to microns, and what the hell this all means for our suit wearing brethren!

Often mistaken with thread count, super numbers, and their neglected cousins below the 100 mark, actually refer to the number of “hanks” that can be spun from a pound of raw wool – a “hank” being a spool of 560 yards. So finer micron wool would weigh less, making a pound of finer wool able to be processed into more spools. So higher number means lower micron, and in turn finer wool and lighter fabric.

How does this apply to microns (and what is a micron!?). A micron, or micrometer, is one millionth of a meter. So an 18.5 micron wool – or a super 100 – would be a fibre that is 18.5 millionths of a metre across. Super numbers tend to rise in increments of ten, dropping half a micron as they go up – so a Super 120’s would be 17.5 microns, and a Super 150’s would be a miraculously fine 16 microns!

An actual table of Super Numbers to Micron weight is listed below;

Super 200’s weighted mean value μ ≥13.26 ≤ 13.75

Super 190’s weighted mean value μ ≥13.76 ≤ 14.25

Super 180’s weighted mean value μ ≥14.26 ≤ 14.75

Super 170’s weighted mean value μ ≥14.76 ≤ 15.25

Super 160’s weighted mean value μ ≥15.26 ≤ 15.75

Super 150’s weighted mean value μ ≥15.76 ≤ 16.25

Super 140’s weighted mean value μ ≥16.26 ≤ 16.75

Super 130’s weighted mean value μ ≥16.76 ≤ 17.25

Super 120’s weighted mean value μ ≥17.26 ≤ 17.75

Super 110’s weighted mean value μ ≥17.76 ≤ 18.25

Super 100’s weighted mean value μ ≥18.26 ≤ 18.75

How does this advantage the suit wearer? For us here in Australia it means that the suit is lighter on the body, a definite advantage in an Australian summer, but lower counts also have their advantages,

which is why many bespoke suits are made in lower count 80’s and 90’s. Higher micron, lower count wools tend to hold a crease well, and are less likely to rumple throughout the day as they are heavier and more draped. Higher count wools also suffer from what makes them desirable – a 130’s or 150’s is undoubtedly a luxury fabric, with a finer, more delicate fibre. Delicate fibres woven closely together are silkier, but still more delicate, making them less able to withstand heavy and repeated wear. A suit in a 110, properly rested is fine for to be worn twice or three times a week, while a 150 would be better served being worn just once a week.

But microns and hank counts are not the final signifier of what makes a good wool – differing breeds of sheep produce differing qualities of wool and the processing of that wool makes for differing qualities of an end product. Just as slow woven, hand picked cotton is better because there is less chance for fibre breakage, and thus longer fibre, smoother hand and better fabric integrity, so can an indelicately woven wool in a higher number be less desirable than a low count from a better mill.

Australian Merino wool is prized as being of the best quality through the world, with many of the world’s innovations in the wool industry coming from Australian farmed Merino. Wool mills are at their best in England and Italy, with the mills of Biella, Italy being renowned for their quality. Names such as Vitale Barberis Canonico, E. Thomas and Lanifico Di Lessona are famous throughout the world for the quality of their wools, all labels that Herringbone is proud to work with.


  1. Keep posting stuff like this i really like it

  2. Ethan,
    I always find it amusing that the general public has been eduated to associate lighter fabric as cooler fabric. Unfortunately, this is not always the case since, as you pointed out, the lighter the fabrics, the higher the microns. The higher the microns, the tighter the weave. The tighter the weave, the less breathable the fabric. The conclusion is counter intuitively since these lighter but tightly weaved fabrics can be less comfortable during the warmer months than heavier, open weaved fabrics.

    I find that besides the advantages you mentioned, an unlined s90 to s110 open weave fabric (such as hopsack) works better in summer than the lighter s130+ fabric that are suppose to be summer fabrics.

    Keep up the good work!