Mordants in Solar Jars

"Are you just stuffing plain, dry Merino into those jars of flowers?"
"It'll be alright Elinor, calm down, I've done solar dyeing this way before."
"What, with no scouring and soaking and mordanting, you expect that wool to take up dye properly? You're off your trolley, Beaut." My companion turned away, settled her specs lower down her nose and resumed waving her hoof in time to unheard music.
"I put some dissolved alum in with the water in the jar, so the sun mordants the wool at the same time as releasing dye from the flowers. Great short cut, quick and easy, especially with all this hot weather." I waited for some appreciation of my cleverness, but Elinor was now absorbed in her own work. I pottered over. "What's that you're reading?"
Elinor pressed her lips together and shook her head.
"Stop distracting me, it's only a few weeks til the performance. Were you not listening when I told you I'd be singing a solo for the Tabernacl Choir? I'm learning the score with the Musical Director breathing down my neck. He's such a perfectionist."
"I know, he gives the tenors a really hard time. I'm a bit nervous myself, Ethel Smyth's Mass in D is a big challenge for all of us."
"Oh, you've got nothing to worry about, hidden up the back of the alto section, copying Gwyneth's every note. You relax, go back to your jars and waste good wool for lack of preparation, I shall be totally exposed to the public eye and ear doing my solo and I do not intend to be second rate. Unlike some." At which, she returned to her humming and hoof waving, frowning diabolically at any interruption, even when I just raised my eyebrows and mimed drinking a cup of tea. Stung by my companion's remarks, I wanted evidence to prove that taking short cuts wasn't spoiling my solar dyeing.

I scoured, soaked and mordanted two 10g portions of blended merino and silk tops with 10% alum and put them into two jars, one with a rusty nail to add iron, and filled the jars with water. Then I tore off two more 10g strips of the same tops, giving them no mordant or soak at all before putting them into another two jars, this time with 1g of dissolved alum added to the water as well as a rusty nail in one jar. Finally, twenty Dyers Chamomile flowers were put into each jar and all of them stood together on the shelf in the greenhouse. The dry tops floated up to the top of their jars, but I reckoned they should soon absorb some fluid and sink down.

The sun shone in the greatest heatwave Wales has experienced in decades. Two days later, the unprepared tops were still floating and athough the fluid in their jars was more yellow, it already looked as though the solar dyeing was working better on the premordanted fibres. My companion was still busy trilling away at her solo and I thought maybe I'd go and practice the fiddly bits of the fugue in the Credo.

Five days in and the situation looked even worse for the short cut jars, where the wool still floated pale above an even more yellow fluid. Time I learned all those Amens in the Gloria. After a week, the unprepared fibres at last seemed to be taking up some colour and I had hopes that the all in one mordant and dye jars would work fine in the long run. No harm in giving all the jars a good shake, just to mix things up.

Two solid weeks of hot sunshine and temperatures up to 27 degrees Centigrade are almost unheard of in Wales.
"Come out of that greenhouse, Beaut. You'll boil yourself alive." I started guiltily and stood in front of the jars as my companion sauntered in. "More solar dyeing is it? Something I ought to see, perhaps?" 
No getting away with this, I had to explain the experiment.
"Looks like the mordant in the water is holding the dye in your short cut jars."
"I think the wool in them looks just as yellow as the premordanted wool now though, Elinor."
"Really? Shall we have a look?"
Before I could protest, the jars had all been emptied out onto the lawn.

"Well, the wool has all gone yellow, Elinor."

"Mmm, but not equally yellow. The short cut jars have not worked as well, the dye is second rate. And your rusty nails haven't modified the colour much."
"Maybe they didn't have long enough to dissolve iron into the water. The wool went really green with rusty nails in those jars of Dyers Chamomile that got left for months. It might have helped if these jars had been left a bit longer."
"Best you tidy this lot up. I must dash. Mustn't keep the orchestra waiting." My companion headed off to another rehearsal, calling over her shoulder, "Don't leave those nails on the grass, they'll bugger up the lawn mower."

I have to conclude that all in one mordant and dye solar jars don't work as fast as ones with premordanted fibres. Unless I intend to wait for months to get this much solar heating into a jar in an average Welsh summer, the short cut method isn't really a short cut at all. Possibly, the results would be second rate how ever long I waited. Now they are dry, I can see that the silk fibres have dyed more strongly in the short cut jars, making a deeper contrast with the pale yellow wool and a good airing has promoted the saddening effect of iron from the rusty nails.

If the results aren't quite what I had hoped, at least in the meantime I've prepared thoroughly for the choir's big event this Sunday. I'm intrigued to know exactly what Elinor will be singing. There's Always the Sun?