Merino Wool Through My Eyes

Part Two: What Does Micron Count Really Tell Us?

When people begin their journey into feltmaking, they naturally look for clear answers.

Which wool is the softest?

Which one felts the fastest?

Which Merino should I buy?

Very often, the answer seems surprisingly simple:

The finer the micron count, the better the wool.

It is one of the first things we learn.

We hear it from teachers, experienced feltmakers, manufacturers and suppliers. Gradually, it becomes something we rarely question.

And that is perfectly understandable.

At the beginning, we all need a point of reference.

For many years, I believed exactly the same thing.

Then, little by little, experience taught me that the answer was far more complicated.

One of the most memorable moments in my own journey came when I had the opportunity to work with a tiny sample of 13–14 micron Merino.

It was only a small piece, certainly not enough to fully understand the material, but enough to leave a lasting impression.

The fibres were incredibly delicate—almost weightless in my hands.

It was one of those rare moments when you realise just how extraordinary natural fibres can be.

Most feltmakers will never need wool this fine, and neither have I. But experiencing it changed the way I looked at micron count. It made me realise that fineness alone does not define the value of a material.

Generally speaking, Merino between 15 and 17 microns is considered one of the most luxurious grades available.

Around 18–19 microns is commonly described as Superfine or Extra Fine Merino, and this is the range I personally work with most often.

Merino around 20–21 microns is usually classified as Fine Merino, while fibres from approximately 22–23 microns onwards become increasingly suitable for projects where strength and durability are more important than exceptional softness against the skin.

These descriptions, however, should always be treated as useful guidelines rather than absolute rules.

Different producers, industries and countries may use these commercial classifications slightly differently. The terminology is helpful, but it should never replace our own understanding of the fibre itself.

Before we go any further, it is worth asking a simple question.

What Is a Micron?

A micron is one millionth of a metre.

It is the unit used to measure the diameter of an individual fibre.

When we read 19 microns on a label, we are looking at the average fibre diameter measured from a representative sample. It does not mean that every single fibre has exactly the same thickness.

Like every natural material, wool always contains variation.

And this is where I believe one of the most common misunderstandings begins.

Many of us start to think of micron count as a measure of quality.

In reality, it is nothing more—and nothing less—than a measurement of fibre diameter.

It tells us that one fibre is finer than another.

It does not tell us that one fibre is necessarily better.

Micron count helps us estimate several important characteristics.

It gives us an indication of the potential softness of the fibre.

It suggests how comfortably the wool may feel against the skin.

It influences, to some degree, the flexibility, drape and refinement of the finished felt.

These are valuable pieces of information.

But they are only part of the story.

One point is especially important to understand.

Micron count does not determine the thickness of the felt you create.

A light, almost transparent fabric and a dense sculptural felt can both be made from exactly the same 19-micron Merino.

The final result depends on the number of layers, the layout, the amount of fibre used, the degree of shrinkage and, above all, the decisions made by the feltmaker throughout the process.

Another question I am often asked is whether we can always trust the number printed on the label.

If the fibre has been professionally tested, its diameter has been measured using internationally recognised laboratory methods.

However, we do not buy laboratory reports.

We buy wool.

And wool is a living natural material.

A micron value is always an average.

Within every batch there will be fibres that are slightly finer and others that are slightly coarser. The way the fleece has been selected, sorted and prepared also contributes to the character of the finished material.

So yes—the number is useful.

But it is only one characteristic of the fibre.

An important one.

Not the only one.

As feltmakers, we often hope that choosing the “right” micron count will automatically lead us to better felt.

In reality, our journey is rarely that straightforward.

With experience, we begin to understand that two feltmakers can work with exactly the same wool and still produce completely different results.

Likewise, two Merino wools carrying exactly the same micron count may behave in completely different ways.

That is why I no longer choose wool based solely on the number printed on the label.

I see micron count as the beginning of a conversation with the material—not the conclusion.

Micron count tells us how fine a fibre is.

It does not tell us how that fibre will behave in our hands.

And perhaps that is the most important distinction of all.

That is where our real conversation begins.

-------------------

  If you are looking for Merino Wool, explore materials of my trusted supplier - DHG.