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Barrel Materials

I touch on materials in the discussion of the fountain pen’s development, but I want to expand on the properties of the various materials a little.



My land-line. I am a traditionalist in many ways.

What it is:A very early thermoset plastic; rather than becoming gooey when heated, it starts out as goo and hardens when heated.  Devised in 1907 by Leo Baekeland, it was used in a vast array of durable goods throughout the 2oth century, and if rumour is true is still used for the caps on bottles of Quink.
Why it’s good:  It can be made transparent, allowing for visible ink supplies, and is as easily machined and no less durable than hard rubber.  Lacks the incendiary nature of celluloid.

Why it’s bad:  It’s no more durable than hard rubber.  To be really tough, Bakelite needs to have strengthening fillers mixed in.  With the right fillers in it, it’s strong enough to be used in public telephones, but in the simpler transparent formulations it’s much more breakable than celluloid.


What it is:  Ex-lava.  At the moment, only Visconti uses this to make pens from, and there’s no telling what possessed them to try it.

Why it’s good:  Extremely comfortable to hold; a grippy texture one reviewer described as “peach skin”, and it apparently wicks away hand-generated moisture.

Why it’s bad:  Matte finish may be off-putting for some.  Very damn expensive.


What it is:  A plastic based on milk proteins.  Also known as “galalith”

Why it’s good:  Casein pens are some of the prettiest pens; the colours are vibrant and the possibility for marbling them together make for some startlingly handsome pens.

The looks are almost worth the peril….


Why it’s bad:  It swells up and goes gooey if it gets wet for any length of time, which makes reservoir failure somewhat of a disaster and cleaning at very least slightly troubling.


What it is: A plastic based upon cellulose– rather than waiting untolds aeons for plants to be transformed by geologic processes into petrochemicals, they’re transformed by the application of some chemicals into useful plastics.  Which chemicals has some bearing on the exact nature of the stuff, of course, and there’s three main variations one is apt to brush up against:

  • Cellulose Nitrate:  Cellulose and nitric acid, with a few other ingredients like camphor.  Without those few other ingredients, you’ve got nitrocellulose, which is the propellant used to fire the main guns on battleships.  Technically, this is “real” celluloid, and the next two entries are only related materials which shouldn’t use the name.  This stuff was used in in the Victorian era and into the mid-20th century with the sort of mad abandon we now apply to petrochemical plastics– it’s hard to name something that wasn’t made with it.
  • Cellulose Acetate:  This more or less replaces the nitric acid with acetic acid.  More commonly used in a fibre form (cloth, ribbon, and so on), it does appear in some things that people look at and think merely “Huh, plastic,” like buttons.  It was apparently the original Lego material, too.
  • Cellulose Propionate:  Propionic acid, this time, and I admit to being too weak in chemisty to know what that is.  Found mainly in Sheaffer pens of the Touchdown era (under the trade name “Forticel), like the acetate version it does appear in modern uses most folks will never notice.

Why it’s good:

  • Nitrate:  Once it was worked out how to colour the stuff, it became just about the prettiest thing possible to make a pen out of.  It smells nice, thanks to the camphor, feels pleasant in the hand, can be transparent or not, isn’t very bothered by getting wet, and is much less likely to break than hard rubber.

    Celluloid nitrate in a relatively restrained degree of festivity

  • Acetate:  Most of the same attributes of the nitrate, although it trades off being less pretty for substantially lower risk of conflagration.  Extremely resistant to moisture
  • Propionate:  Can be transparent, it’s the most impact-resistant of the three, and the least likely to loose its plasticizers.



Why it’s bad:

  • Despite the way it looks, it’s not at all sweet

    Nitrate: Nearly an explosive; if exposed to an open flame, it burns fast and hot.  Given to reacting to gases released when ink and rubber combine, and thus darkening.  Can shrink, and if a slight error was made in the composition it disintegrates into a pile of what looks like sugar.  Can be stained by prolonged ink contact, and may go cloudy if left in water too long or exposed to warm water.

  • Acetate: Less pretty, and until recently could not be made transparent.  More brittle than nitrate, so more easily broken.
  • Propionate:  Rather given to shrinkage, and is very susceptible to weathering and discolouration– it may even absorb water if left exposed too long.


What it is:  Baked clay,  just like the plates in the cupboard.

Why it’s good:  There’s a long history of ceramics use, and we’ve learned to do some fairly clever things with it.  Smooth finishes and attractive colours are relatively easy to produce.

Why it’s bad:  Ever dropped a plate?  Ceramics are quite intolerant of impact forces.  There are occasional toxic and radioactive elements in the glazes, but in a pen this is more of a problem for the person making it than the user.  Potential for being too heavy.


What it is:  Usually brass, although sometimes steel is used.  Aluminum is not entirely unknown but is more usually limited to caps only.  Metal bodied pens fall into one of the following subsets:

  • All metal: This is not the same as all the same metal.  Steel bodies will often be merely brush-finished or sand-blasted and left as they are, and there are a few makers offering pens with a solid silver body.  Brass is almost never left out where it can be seen, but is rather coated with another more attractive metal.  This coating is done in one of two ways:
      • Plated:  A very thin coating of metal, usually applied in modern items by passing a charge through a solution to draw atoms of the substance onto the object to be plated, although heat and pressure have also been used.  Plating in pens has been done with with chrome, nickel, rhodium, platinum and gold (as well as some mysterious gold-coloured substances in less expensive pens).  In aluminum, the process is slightly different, and an anodized aluminum can be just about any colour.

    Skyline cap – “YGF” is Yellow Gold Filled

    • Filled: A rather thicker application of a coating metal, done by pressure.  This is most often done with gold (“rolled gold” is synonymous), and pens or parts involving this sort of application will usually have a little notation on them reading something like G.F. 1/10 18K; The G.F. just means “gold filled”, the K number indicates the purity of the gold (24 karat is pure, 18k and 14k are the most commonly found), and the fraction indicates how much of the weight of metal is actually gold.  Since gold is rather heavy, this means that the thickness of gold is much less than the thickness of the underlying metal.
  • Overlay:  a casing of metal around another material.  The term is used mostly for the elegant cages of gold or silver found wrapping early rubber pens.  This sort of application can be found in modern pens as well.  A lot of modern pens which appear to have a metal body might be technically thought of as an overlay, as that metal shell encloses a plastic body.  Historically, there have been similarly all-engulfing overlays.
  • Lacquered: A very popular modern application, which allows the use of a brass barrel without letting the brass show.  Since lacquer is really just a fancy paint, this allows for a lot of different appearances, some almost as attractive as celluloid.
  • Cloisonné: Enameling laid into a metal base.  The term comes from the French word for the cells in a beehive, because there are little metal walls keeping sections of enamel separate; “cloister” is the nearest English word, and of quite similar meaning.
  • Appliqué:  This isn’t necessarily the right term, but I wanted something of a catch-all for diverse foils and wrappers that can be applied to the outside of a pen.  There are even some with leather exteriors.

Why it’s good:  Humanity has been working metal for some thousands of years.  We’re reasonably good at it now.  Metal is strong, and not very given to fracturing under the sort of stresses a pen may find itself under.  It is also attractive when polished.

Why it’s bad:  Metal is less resilient than other materials; while it doesn’t break, a minor impact can leave an unsightly dent, as well as a chip in lacquer.  Plating can be worn away by polishing, and even gold filled items can wear through with use.  Many metals corrode if exposed to ink.  Metal readily passes heat through to the reservoir, which can lead to ink dripping.  Metal is heavy; this is a more subjective complaint than the others, as many people find a heavy pen a comfort, but I feel that excess weight is foolish in a pen that needs no pressure to write.

Modern Plastics:  A brief editorial note

Petrochemical plastics are getting to have something of a terrible reputation.  Part of this comes from the use of some chemicals in their creation without pursuing the potential consequences, like using BPA in food containers, but the greater part comes from a general mis-use of plastics.

Plastics are extremely durable materials, very little given to breaking down in short order in most of the ecosystem.  Because they are very easy to mass produce, and because of the nature of the consumer culture which developed in North America after the Second World War (which I rant about further in the History department), plastics have been applied to disposable items which people have happily disposed of.  Unlike past disposables, which were very few and largely biodegradable, disposable plastics hang around for ages and grow into great unsightly menaces like the horrible floating continent of trash in the Great Pacific Gyre.

What plastics should be used for is durable items.  When used in something that is meant to last, there’s little to argue against plastics.  The next several items in the materials roundup are petrochemicals, without a doubt, but when applied to fountain pens they are petrochemicals which can at least hold their head up.

Plastic: ABS

What it is: Acrylonitrile butadiene styrene.  That’s not actually helpful, is it?  ABS can be thought of as an alloy of plastics, as steel is an alloy of metals, and as steel is rather stronger and more useful than its individual elements, ABS is a rather good plastic.  It is impact resistant, and can be applied to injection molding and machining.

Why it’s good:  Resistant to impact and shattering.  Inexpensive to produce.  If worst comes to worst, it is also readily recycled.

There’s a reason this pen has so much trim on it

Why it’s bad: Doesn’t mold for fine details well, and is given to scratches.  It has an unavoidable slight translucency which suggests cheap plastic.

Plastic: Acrylic

What it is:  Polymethyl methacrylate.  Known also under the tradenames Plexiglas, Perspex and Lucite, it’s a very strong plastic which can be molded and machined.

Why it’s good:  Extremely resistant to caustic and acidic fluids, it is essentially immune to ink’s effects.  Light and strong, it polishes to a good lustre and resists scratches reasonably well.  Can be coloured or transparent.

Why it’s bad:  Somewhat expensive.  Brittle, compared to polycarbonate.

Plastic: Polycarbonate

What it is: A family of extremely strong plastics, including Lexan, Makrolon and Makroclear, amongst the uses of which is bullet-resistant windows.

Why it’s good:  It’s an extremely strong plastic, and is so much less brittle than acrylic that it can be cold-worked like a metal; one may call it shatterproof, in the shape of a pen, with a straight face.  It can be transparent or coloured.

A clever way to avoid scratches – make them the finish itself

Why it’s bad:  It’s expensive.  Bisphenol-A may be involved in its making, depending on when and where the example was made.  The lack of brittleness brings a lack of hardness, and it is prone to scratching without a special coating.  A special coating is also needed to prevent damage from long-term UV exposure.

Plastic: Polystryene

What it is:  One of the earlier petro-plastics, a lot of people will be familiar with it from model kits.  While it can be machined, the usual means of production of polystryene items is through injection molding.

Why it’s good:  It is relatively hard, and so is resistant to scratching and capable of holding fine details in molding.  Clear and coloured forms can be had.  It is inexpensive.  It is chemically inert, which means it isn’t troubled by prolonged contact with ink.

Why it’s bad:  Hardness and brittleness go together.  It is rather less resistant to breakage than ABS.

Plastic: Poly Vinyl Chloride

What it is:  A rather early plastic, discovered in the 19th century, but not commercially used until the late 1920s.  It’s a protean stuff, capable of being flexible or stiff, and sees use in just about everything; house siding, clothes, sewage pipe….

Why it’s good:  Quite inert chemically, takes colours well, and resilient in the face of impact.

Why it’s bad: Rather toxic if burnt, and production of it generates PCBs.  Tends to look rather more “plastic-y” than some other plastics.  Can degrade  and go soft.

Hard Rubber

What it is: Just what it sounds like– rubber.  Unlike most of the rubber one encounters today, this has been treated in the vulcanization process to become quite hard.  When in mint condition, the only way to tell it from plastics is from the sulfurous smell it can give off, and even this might require a little warming; if unsure, try rubbing the tail of the pen against a palm and then sniff hand rather than pen.

Why it’s good: Apart from being readily available in the early years of pen-making, it has some assets as a pen material.  It is quite heat resistant, meaning that it is unlikely to be damaged by heating when under repair, and it is extremely light, preventing pocket damage and writing fatigue.

Why it’s bad: When rubber is this hard, it is extremely brittle, making chipping or outright destruction much more likely than with most other materials.  It is also extremely succeptible to discolouration through exposure to UV light and warm fluids, passing through stages of olive and grey and eventually going into cocoa brown.


What it is:  Actually, it’s a finish, rather than a pen-barrel material, a sort of traditional Japanese lacquer.  It’s most commonly applied to hard rubber in extremely expensive pens, and is the medium for maki-e painting.  I include it here only because one occasionally hears of urushi pens, and I didn’t want people to be uninformed.

Vegetal Resin

What it is:  As far as I can tell, it’s yet another variant of celluloid, with a clever name; a plastic substance based upon plant material.

Why it’s good:  It’s non-explosive, and can make some claims towards eco-friendliness (although given the sort of processing it takes to make celluloid, I’m not altogether convinced).  Jolly colours are available.

Why it’s bad:  Just how biodegradeable is it?  Some examples are reported to “smell funny”, but that’s a subjective thing.


What it is:  Just what it sounds like, a lump of tree.  While frequently used for home-made kits put together by lathe enthusiasts, there are occasional forays into its use by mainstream manufacturers.  Waterman, for example, have a wood-bodied version of their high-end Sérénité.

Why it’s good:  It looks good, and it feels good in the hand.

Why it’s bad:  It’s porous, and I suspect an incautious filling will do mischief to the finish.  Wood is relatively soft and compressible, and so both dents and scratches can result from incautious handling.

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