Mosaic and Micromosaic Terminology

4 types of mosaic: traditional mosaic (blue) 1cm average tesserae, vermiculatum micromosaic (fish) 4mm or less average, floral venetian micromosaic (right brooch) 1-3mm average, roman filato micromosaic (left landscape brooch) 0.1mm average.

There is not much information available online about mosaic terminology, particularly micromosaics. Most of the information I have found is aimed at antiques collectors and tends to overlook the techniques or materials used, and certainly doesn't consider all the factors related to mosaics in general. In this article, I aim to provide some clarity.

To compile the terminology below, I consulted a wide range of experts in the field, including museum curators from abroad, renowned mosaic historians, local Italian mosaic restorers, archaeologists, and artists specializing in both mosaics and micromosaics. I will focus on micromosaics and Filato mosaics, as this is my area of expertise. In this article, you will find a useful list of terminology. Keep scrolling for detailed definitions and explanations.

Bullet List Glossary of Micromosaic Terminology

• Mosaic: Umbrella term for any work of art that includes multiple materials in an organized surface, generally stone, glass, ceramics, cement etc.

  
  

• Opus Vermiculatum: Modern term referring to a style of mosaic featuring small stone and glass tesserae made in Roman and Byzantine times.

  
  

• Micromosaic: Umbrella term used to speak about small sized mosaics with tesserae ranging from 4mm down to fractions of a millimeter. Thus, anything from Vermiculatum to Filato micromosaics.

  
  

• Filato Mosaic or Roman Micromosaic: Term referring to a specific technique and style of micromosaic that requires melting and pulling glass into filaments to make micromosaics, sometimes but not always ground and polished and grouted with coloured wax.

  
  

• Venetian and Florentine micromosaic: Newer type of micromosaic that is and was produced in Florence and Venice for tourism using generally floral designs and larger multicoloured tesserae. They are generally not ground, polished or grouted with wax.
  

In Depth

Mosaic: Mosaic is a generic term to talk about a multitude of different things.

An ancient mosaic is an organized surface with different reflections of light. Materials like stone or glass are often cut into cubes in varying sizes and placed in an organized fashion onto a surface. there are many methods of making mosaics and it is not always necessary to cut the materials sometimes they are broken or used whole.

Roman and Byzantine mosaics had cubic tesserae (individual elements of a mosaic) that ranged in sizes from over 2cm in floor mosaics down to tiny, fractions of millimeters. Ancient Mosaics however, are generally made in vitreous paste (often called smalti, a type of opaque glass) and/or natural materials (like stone and marble). These were cut down by hand with hand held tools called a hammer and a hardie. All ancient mosaics had andamento which is a term that describes the surface organization of a mosaic. Andamento is an Italian term which doesn't have a proper English translation but can mean the direction or flow of the tesserae. When looking at an ancient mosaic you will see a well defined organization to the tesserae in lines. These lines flow or have an andamento or a direction to them. Modern mosaics often do not have andamento and the materials can literally be anything including, but not exclusive to, ceramics, stained glass, beads, pebbles, recycled materials, plastics, seeds, insect wings etc. Tesserae can be of varying sizes, as can the mosaics themselves. Mosaic is a general term to talk about a variety of different techniques and sizes. See below. Opus Vermiculatum: Opus Vermiculatum is a modern term not found in ancient texts and is used by scholars and historians to talk about a specific style of mosaic. It refers to a technique of the most refined roman and byzantine mosaics which used minute tesserae from between 1-4mm to make a precious mosaic insert for a floor called Emblemata. Materials used were mostly stone and marble. They were often symbols of a family’s wealth.

Micromosaic:

Micromosaic is a modern term said to be coined by the Gilbert family as they were avid collectors of micromosaics, a collection which is now housed at the Victoria and Albert Museum in London. The term micromosaic doesn't have a set English or Italian definition since there are a variety of objects that fit in the overall definition. If we look at the term itself a micro-mosaic is a very small mosaic or a mosaic with very fine tesserae. In my experience, experts in the sector, Italian mosaic restorers and producers of reproductions, tend to call any mosaic with tesserae 4mm or less a micromosaic regardless of what it is made with or how it is made. Filato Mosaic / Mosaico Minuto (minute mosaic) / Roman micromosaic These are all terms that describe a specific technique and style of mosaic making that was invented in Rome, specifically the Vatican during the late 1700s early 1800s. The technique requires the artist to melt glass at high temperatures to stretch it out into filaments that are then scored and snapped to create the tesserae. These are then placed with tweezers into a special binder called stucco. They were often meant to imitate paintings. The finished mosaic was historically, often but not always, ground down and polished, as well as grouted with a coloured wax. The technique continued to be used outside of the Vatican by the Vatican Micromosaic artists as a means to make extra money selling their craft to tourists of the Grand Tour. As time went on the laborious task of grinding, polishing and waxing a piece became less and less used while tesserae got larger and multicoloured to make work quicker.

Venetian and Florentine Micromosaic

The type of mosaic jewelry produced in Venice but also Florence is and was a chunkier more industrial type of micromosaic. The "filati" are generally industrially pulled by machine, made like spaghetti in a factory. They tend to be fairly uniform in size and quite a bit larger than traditional Roman micromosaic glass filaments. They also often have multicoloured rods for leaves, flower petals and decorative borders making it quite a bit easier and quicker to produce floral designs. These industrial style mosaics are now mass produced for tourists, it is unclear where they are being produced but the main productions now seem to be in Florence. These mosaics are currently undefined. They do not have their own terminology and have yet to be studied in terms of historical significance to the mosaic and micromosaic world.

It is however important to note that Micromosaic artists will sometimes imitate the chunkier floral style making each element by hand without buying industrially produced filati. This makes it even harder to distinguish between these types.