How to Make Lettered Rock Content from the guide to life, the universe and everything

How to Make Lettered Rock

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A section of rock with the words 'how to' running all the way through it.
A fellow took my photograph, it cost one and three.
I said when it was done, 'Is that supposed to be me?'
'You've properly mucked it up - the only thing I can see
Is my little stick of Blackpool Rock.'

George Formby - With My Little Stick of Blackpool Rock

Lettered rock. A cylinder of hard, boiled sugar about a foot long and an inch in diameter, pink on the outside, white on the inside. But look at the end of it - there's a ring of bright red letters which spell out the name of the seaside resort where you bought it and which miraculously runs throughout the length of this confection.

How on earth do they do that?

The Recipe

A pot full of boiling sugar, slowly congealing into rock.

Like most sweets, rock - lettered or otherwise - begins as a mixture of water, sugar, and glucose syrup which is boiled until it reaches a certain temperature - in this case around 295ºF (146ºC). When ready, the batch1 of hot syrup is poured onto a polished metal slab2 to cool it down. These slabs are made in such a way that the interior is hollow, and they can be heated or cooled by opening one of two inlet valves and running either steam or cold water through the inside of the slab. The slab is six feet times three feet times two inches thick (two metres times one metre times 50mm), and is very heavy indeed. Steel bars roughly one inch square in section are placed on top of the slab around its edges to prevent the syrup from spilling onto the floor.

Flavouring - traditionally peppermint - is added and mixed into the batch, which begins to thicken as it cools down. After five or ten minutes, it will be less like a liquid and more like a very thick batter, allowing it to be handled, with much skill and respect - it's still hot enough to inflict a very nasty burn to bare skin. At this point the batch is divided into two parts in a ratio of about six to one, and red colour added to the smaller part.

As it cools down even further, the batch becomes more like bread or pastry dough and is easier to manipulate, although still quite hot. Once it reaches this stage, the sugar-boiler3 will shut off the cold water which has been taking heat away from the slab, and open the steam valve to keep it - and therefore the batch - at a temperature of about 150ºF (65ºC). If the temperature of the batch was to fall much below that, it would harden and become unworkable. Sugar is not thermoplastic - once it has cooled and hardened, it can't be softened by reheating.

Two people stretching the soft rock into long cylindrical pieces.

It takes two people to make lettered rock - a sugar-boiler and an assistant, and at this point the assistant will be given the larger, uncoloured portion of the batch to 'pull'. Pulling used to be done manually - the batch was rolled out into a long, thin sausage and then draped over a large hook which was fixed to a wall. Being soft and pliable, the batch could be pulled on and lengthened, then wrapped over the hook again. Doing this dozens, even hundreds of times for ten or fifteen minutes would produce the same result which pulling machines now found in most sweet factories can achieve in under a minute. Pulling incorporates air into boiled sugar mass and encourages the growth of minute sugar crystals. This turns uncoloured sugar mass white, lightens the shade of sugar mass which has been coloured, and in both cases turns it either translucent or opaque, depending on how long it's pulled for.

Once pulled, the now white and opaque sugar mass is returned to the warm slab and covered to stop it cooling down and hardening. The sugar-boiler will by now have divided the smaller, red portion of the batch into two parts in a ratio of about three to one, and the assistant is sent back to the pulling machine with the larger of these two portions. This is pulled for a shorter time than the white part was, turning it translucent pink. It's then returned to the warm slab and covered.

Putting it Together

A pair of gloved hands shapes the soft rock into place.

This is where the real skill begins. The letters have to be formed and then put together to spell out words, and the whole thing assembled to make the product which many of us recognise. It can take anywhere from five to ten years to learn how to do this well enough to add the title 'lettered rock-maker' to that of 'sugar-boiler'.

By now, everything will have been moved from the slab where the batch was originally poured to a pair of heated slabs placed end to end to make a working surface 12' (3.75m) long. After flavouring, colouring and pulling, here's what has become of the batch:

  • A large, opaque white portion which has been pulled
  • A smaller, translucent pink portion which has also been pulled, but not quite so much
  • A much smaller, clear red portion which has not been pulled at all

Building the Letters

The simplest way to get a grasp of how the letters are made and then formed into words is to think of them as a child's alphabet blocks, except instead of a cube two inches by two inches by two inches with a different letter on each face, these are two inches by two inches... and six feet long, with a letter on one end which runs throughout the length of the block and reappears on the opposite end4. Viewed end on, the letter itself is made of clear red sugar surrounded by opaque white sugar. Any spaces within the letter - such as 'P' or 'O' - are also filled with white sugar mass.

Let's start off by describing the easiest letter to make - 'I'. It's formed by cutting off5 a piece of the clear red portion - enough to stretch into a thin strip six feet (two metres) long, two inches (25mm) wide, and about half an inch (12mm) thick. Two pieces of the white portion are stretched out to the same length and thickness and laid on either side of the red strip to form layers which when viewed end on resemble a jam sandwich - in other words, a letter 'I' lying on its side.

To glue the different pieces of each letter together, the faces to be joined are simply wiped with a damp cloth - water is all that's needed to stick sugar together.

Let's take another easy one - the letter 'T'. The procedure is almost the same as that for forming an 'I', but in this case an extra piece of the red portion is needed to form the top bar of the 'T'.

Letters such as 'W' and 'A' are somewhat harder because angles are involved, but the process is essentially the same - long thin strips of red sugar are surrounded by blocks of white. In such cases, the sugar-boiler has to form the white part of the batch into triangles and odd shapes such as a rhombus, instead of squares and rectangles. Letters involving curves such as 'G' and 'S' are the hardest of all - the procedure for making those is far too involved to describe in words and has to be seen or explained with diagrams to be fully understood.

After constructing each letter, the sugar-boiler places the long bar of warm sugar mass between two pieces of wood at least six feet long to keep its shape. Remember, this sugar mass is being kept soft enough to work, and if left on the slab without any support at the sides it would slump under its own weight and become flat6. As more letters are made they are placed beside each other on the slab, each one separated from its neighbour by a piece of wood.

Constructing the Words

As with Blackpool rock, it's usual to find the name of a town and the word 'ROCK' in a stick of lettered rock, and the letters are almost always in upper case. Let's imagine that on this occasion the sugar-boiler will be making rock from that other British seaside town strongly associated with the sweet. The words which are to be incorporated into it will be 'BRIGHTON' and 'ROCK'.

While the sugar-boiler is making the letters, the assistant will prepare a number of thin strips of white sugar mass about half an inch thick, two inches wide and six feet long - these will be the spaces between the letters. Working quickly, the sugar-boiler takes each letter of the first word, and once again moistening the faces with a damp cloth, joins them together with one of the previously prepared 'spaces' separating each one, thus forming a 'plank' six feet long, two inches thick and roughly 17 inches (38cm) wide. This is slid over to the assistant who places wooden battens at either end of the word and along each side7, again to stop it slumping, while the sugar-boiler starts work on the second word, constructed in exactly the same way.

When all the letters have been made and the words are complete, two more pieces of the white portion are stretched out to the same length (six feet) and thickness (two inches) as the letters to make the spaces between the two words. These width of 'fillers' will depend on the total number of letters in the words - the longer the words the shorter the filler. Each of these is joined to one of the completed words on their long edge, and then these are in turn joined to each other to form a large, flat piece of sugar mass six feet long, two inches thick and roughly three feet (one metre) wide, and which when viewed on end presents the pattern:


The word 'ROCK' is usually turned upside down, for reasons which will become apparent soon.

Assembling the Rock

If the sugar-boiler has managed to get all the calculations right, there should be enough of the pulled white portion of the batch left to make two more shapes - a cylinder six feet long and about 12 inches (30cm) in diameter, and another flat piece six feet long, about three and a half feet (105cm) wide, and one inch thick. The translucent pink piece has so far remained untouched.

The 'BRIGHTON[FILLER]ROCK[FILLER]' construction is turned over and the uppermost surface moistened. The cylinder of white mass is laid on top of it, the edges are pulled up and around the cylinder enclosing it completely, and joined together by moistening with the damp cloth. This is why one of the words is turned upside down - so that when the end of the stick of rock is viewed, both of the words are the same way up.

This is then placed on the plain flat piece of white which is in turn wrapped around it in the same manner. In the meantime the assistant will have stretched out the pink portion of the batch into a flat piece long enough and wide enough that the whole assembly can be wrapped in it, giving the familiar pink layer around the outside of the rock.

This entire process probably takes longer to explain than it takes to carry out. An experienced rock-maker with an equally experienced assistant can complete a batch of traditional lettered rock from pouring the syrup to wrapping it in the pink portion in less than half an hour. Here's a page which shows some of the stages already explained and a few more still to come, although these people are making plain, not lettered rock.

Turning it into Sticks of Rock

A person in the process of rolling the rock into shape.

The skilful part may be over, but here's where the hard work begins. This huge cylinder of sugar weighing up to 100lbs (50kg) has to be turned into either several hundred sticks of rock 12 inches long and one inch in diameter, or 100lbs of pieces of chopped rock about one inch long. It used to be done entirely by hand - the assistant working at a heated slab, laboriously rolling the batch backwards and forwards to keep its round shape, and the sugar-boiler pulling on one end of it to stretch it out to the required thickness. As the rock was pulled from the end of the batch, more assistants would begin rolling it on either a stone or a cooled metal slab, again to keep its round shape, and the sugar-boiler would break off six to ten-feet lengths by tapping the rock with a metal rod about the size of a large screwdriver blade.

By the time the entire batch was pulled out, the assistants at the cold slab would be busy rolling dozens of lengths of rock backwards and forwards until they cooled and became hard enough to support their own weight without becoming misshapen. That might take between ten and 20 minutes depending on how warm it was inside the factory.

Once cool and hard, the rock was chopped to the required length - sometimes by hand, sometimes by running it through a simple machine which cleanly chopped the ends of each stick - and then wrapped in clear film which was twisted shut at each end.

Many years ago someone devised a machine called a batch-roller to take the hard work out of rolling the batch on a warm slab. A batch-roller has four conical heated metal rollers which rotate first one way and then the other, mimmicking the action of rolling the batch on a slab, and which are arranged in such a way that they cradle the batch and form it into a long thin cone. Instead of the sugar-boiler pulling on the rock from where it exits the batch-roller, modern sweet factories have an arrangement of sizing rollers which do this, and a refrigerated tunnel where the rock is cooled down. Many rock manufacturers, however, still pride themselves on being small concerns which turn out a hand-made product, and although batch-rollers are commonly used, the rock will still be pulled and rolled by hand.

Variations on a Theme

Lettered rock doesn't have to be white and pink with red letters, nor is it always flavoured with peppermint, but that's the traditional combination. Rock with multicoloured stripes on the outside is common, as is rock flavoured with aniseed or artificial fruit flavouring. The appearance and flavour of the rock is limited only by the skill and imagination of the rock-maker. There is a story, which may be apocryphal, that a rock-maker who was not best pleased with his employer once made an entire day's production of lettered rock, each batch containing one of several...colourful phrases explaining what he thought of his boss, before walking out on the job and looking for employment elsewhere.

Whether he found other work as a rock-maker is not known.

1Rock is usually made in batches of between 50 and 100lbs (23 - 46kg).2They were originally marble, until hot and cold metal slabs were devised.3Not the name of the equipment which cooks the sugar, but the job title of someone who makes sweets by boiling sugar syrup.4Of course, some letters - such as 'I' - are narrower than two inches because there's less width to them.5The soft sugar mass can easily be cut with shears.6Once that happens there's no way to rescue it without the letter becoming deformed.7Imagine a wooden frame similar to that used to pour a block of concrete.

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