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What’s my Conway Stewart fountain pen made of?

Conway Stewart fountain pens have long been considered to be some of the best fountain pens ever made. In the years since the company was founded in 1905 and today, there have been astonishing changes in science and technology, so we thought it would be valuable for those with an interest in pen history to read about the changes in materials that have been used to make Conway Stewart luxury fountain pens during that period. 

You will be able to read about the development and introduction of fountain pens from hard rubber, casein, celluloid, injection moulded plastics and bringing you right up to date with the latest cast acrylic materials.

Hard rubber or ebonite

It’s long been accepted that Lewis Waterman was responsible for creating the first fountain pen in 1884 in the USA, enabling writers to have a source of ink and a nib which transferred the ink onto paper in a single piece of equipment.

Yet Waterman’s invention also owed its development to another American and one of the pioneers of motoring technology, Charles Goodyear, who in 1839 discovered that by heating rubber and sulphur together he could make a very durable compound which became known as ‘hard rubber’ or ebonite. Later, he would adapt his discovery to create Goodyear tyres for the motor industry but initially it was used in a variety of other ways.

For example, it was found to be a very suitable material to make pens. Until then, writing instruments had been made from reeds or quills, dipped into ink. Dipping pens had also been made from a variety of metals, including steel, but regulating the flow of ink onto the paper was always a problem.

By 1884, pens were becoming more and more popular, so when Lewis Waterman created the first fountain pen, he used hard rubber for the body of the pen, while capillary action smoothly drew ink from a reservoir in the hard rubber tube to the fountain pen nib and then onto the paper.

When Conway Stewart was first formed in London in 1905, hard rubber fountain pens were being widely used both in the USA and across Europe. Frank Jarvis and Tommy Garner, the two founders of Conway Stewart, had experience in the fast-growing pen industry and although they initially imported pens from the USA, or purchased them from other British pen manufacturers, they soon decided to manufacture their own pens. 

In 1912, they opened their first factory in Southwark Street, London. Here, they quickly developed their own pen-making skills either using components bought from the USA or, increasingly, manufacturing their own pens using hard rubber or vulcanite which they purchased from companies such as Morgan Ebonite in Battersea, London. (Vulcanite was another name for hard rubber, named after Vulcan, the Roman god of fire.)

Hard rubber continued to be used by Conway Stewart for some of its pens through the 1950’s and into the 1960’s.

Here’s your chance to own a rare Conway Stewart pen made from hard rubber!

You may be surprised to discover that you can still acquire a Conway Stewart hard rubber pen! When Bespoke British Pens purchased the majority of the stock from the liquidators of Conway Stewart Limited in 2014, they discovered a small number of hard rubber blanks which had been turned in the Plymouth factory specifically for a small edition of Marlborough luxury fountain pens. These historic fountain pens have now been assembled and completed to the best modern standards and are available to Conway Stewart fountain pen collectors and enthusiasts. This is probably the last chance for you to own a piece of fountain pen history! Explore the Marlborough collection, our most popular pen from this collection is: Marlborough Vintage Black Ebonite Gold or have a look at the Marlborough Vintage Woodgrain for a very unique style.


Launched in 1923, the first pen manufactured by Conway Stewart from material other than hard rubber/ebonite was the diminutive ‘Dinkie’ which was made from casein, a by-product of milk.

In the UK, casein was supplied to Conway Stewart in rods (as opposed to the tubes of hard rubber previously used) by a specialist plastics manufacturer, British Xylonite. The rods were hardened by soaking them in dilute formaldehyde so they could be turned on a lathe to create the right shape for a pen. The main feature of this type of rod was the almost iridescent colour effects obtained by British Xylonite’s highly skilled colour technicians. Suddenly, Conway Stewart fountain pens were available in a stunning array of colours, not just the rather austere black or wood grain of the hard-rubber pens.

The Dinkie range reflected the British post-war optimism of the Roaring Twenties fuelled by economic growth and great prosperity. They were bright and cheerful and an immediate hit with the pen-buying public.

The introduction of the multi-coloured casein was not universal across the Conway Stewart range. Some models continued to be manufactured in hard rubber/vulcanite throughout the 1930s and 40s and indeed some Conway Stewart pen components continued to be manufactured from hard rubber into the 1950s.

Ironically, when Conway Stewart was resurrected in the 1990’s some of the first pens were manufactured in casein in exactly the same way that pens had been manufactured in the 1920’s!

Conway Stewart Dinkie

The Dinkie
courtesy of "Fountain Pens for the Million page 42" by Steve Hull

Conway Stewart Series 100 White Casein
Conway Stewart Series 100 White Casein



At approximately the same time as the first casein pens were being manufactured, British Xylonite also supplied Conway Stewart with another new material – celluloid. Celluloid tube was made using bi-coloured or multi-coloured sheets, cut into strips about 1.5 inches wide which were warmed then wound in spirals around a stainless steel core. After being stripped from the core, the celluloid rods were immersed in acetone to create a smooth surface.

Celluloid tube generally had a mottled finish with many colour combinations, although they were not as bright as casein. Conway Stewart purchased celluloid tube in black and in several patterns of marbled green, red and blue. Generally, the different patterns were used for specific pen models.

The manufacture of celluloid tube was discontinued in the mid 1960s, by which time a new method of creating pen bodies – injection moulding – had started to become established across the ranges of many luxury pen brands.

Injection Moulded Plastics

Technological advances during the 1950s and 60s meant that new methods of mass production were becoming available to some of the best fountain pen brands and Conway Stewart soon added new injection moulded pens to their range. The 106 and 106M models were described as ‘of modern design with maximum efficiency’ and featured a new ‘Pressac’ filling system. These were the first of a whole range of pens with injection-moulded plain coloured barrels and slip-on caps that, by 1963, would replace all Conway Stewart models, except the ‘Dinkie’, that had previously been made in patterned casein and celluloid. 

Conway Stewart Injection Moulded
Injection Moulded Conway Stewart Pens & Pencils 1959 – 65
courtesy of "Fountain Pens for the Million page 187" by Steve Hull

Cast acrylic

Today, the majority of Conway Stewart luxury fountain pens are manufactured from a cast acrylic material known as PMMA.  We have found that this material provides us with everything we need for our pens – it holds its colour, it is resistant to weathering and UV radiation, and it can be easily cut, drilled and formed – and, importantly, it is recyclable. 

Conway Stewart Cast Acrylic
Cast Acrylic Models - present day

We hope you have found this article on the materials used to make Conway Stewart pens to be interesting and that it has added to your knowledge and understanding of the history and development of Conway Stewart luxury fountain pens over the past 100 years. You can find much more information about Conway Stewart's history here.

1 comment

Damien Lyle-Stirling

Those 1920s Dinky fountain pens are just gorgeous – especially the green and black one 2nd from the right. I would love to own one. My favourite pen at school in the 1960s was my Conway Stewart.

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