I first learned about clothlets from Thompson's The Materials and Techniques of Medieval Painting. It's sort of generic but encouraged me to do more digging...
'the generic name, however, for cloths saturated in the colours was petia in Latin, and pezza or pezzetta in Italian...
Clothlets were a most convenient form of colours for illuminators. It was only necessary to put a bit of clothlet in a dish, and wet with a little glair or gum water, and the colour would dissolve out of the cloth into the binding medium, forming a transparent stain. A good many colours were prepared in this way for late medieval book painting...' pg 144
From the British Library's Catalogue of
Illuminated Manuscripts glossary we find.
Clothlet: "A piece of cloth impregnated
with PIGMENT (generally a vegetable dye). A portion of such cloth,
when soaked in a little BINDING MEDIUM, releases its colorant and
produces an artist's pigment. Clothlets are called petiae in Latin
and pezze or pezzette in Italian; bisetus folii refers to clothlets
dyed with folium, or turnsole, extract. Clothlets were a convenient
way of carrying or shipping vegetal pigments, and they were
especially popular from the fourteenth century on, with the growth of
the textile trade. Glazes of vegetable dyes were often used to
enhance other colours in book ILLUMINATION, since they created a
rich, glowing, and transparent effect."
You can also find mention of them in this
Getty Publication. Once you start knowing what to look for, you will see a lot of references.
As the addage goes, 'Cleanliness is next to Godliness', so this year I took the recommendation of Jenny Dean in her book Wild Color scouring the linen for my clothlets. I bought 'natural linen' from JoAnne Fabrics. I don't know if it really is natural or it's dyed to look natural.
First I soaked it overnight in clear water filtered through my reverse osmosis (RO)filter. In the morning, the water was light brown. Yuck! So, fabric from the fabric store is not actually the cleanest it can be, got it!
I dumped it out and refilled it with new clean, filtered water and measure 1 tsp dish soap (Dawn) and 2 Tbsp washing soda.
I boiled it for about four hours.
When I pour out the water after boiling it is dark brown and quite dirty!
At this point I abandon the Reverse Osmosis filtered water and rinse in tap water until the water runs clear then wash it twice in my washing machine and air dry the linen.
Looking at the internet it appears that
'finger' was commonly used to measure cloth and '
fistmele' I know from archery. I used my index finger and fist to extended thumb to measure the clothlets. We are in the modern world so I use my fabric scissors to cut the pieces to size. Though we know medieval people had scissors too! Next time I may use '
span' as I see that frequently as I poke around now.
Regardless, I now have clean rectangles of fabric for the next steps. Yay!