I’ll really need to track it down, but I read a fascinating article on the production of the murex dye. First, it wasn’t produced from the shells of the snails, but from a tiny gland in the (head of the?) snail itself, the substance within which reacts to oxygen and sunlight. So, with an accumulation of a vast number of these glands and the juice therefrom, garments would be dipped in the dye. Depending upon how dilute the dye was and how deeply dyed the cloth was, the color could range anywhere from greenish to red to reddish-purple to the deepest darkest violet-purple. The latter, of course, being the most dye-intensive and thus labor-intensive, so the most expensive. I’ll try to find that.

Also, if you’ll notice the tzitziyot (the amazing special bundle of knotted strings) on modern Jewish talliyot (”prayer shawls”), they lack the “blue cord.” This is because the Rabbis couldn’t agree on what color tekhelet actually meant! The Karaites do actually include a blue string in theirs, though. You can buy them here.

On my business cards I have ‘patil tekelet’ (blue cord) written in Hebrew down the side of the card.

The word tekelet is probably best translated as purple or violet. It refers to the color of the dye that is made from the murex shell. But I went with blue because this is the translation in most English versions. This is also why there is blue in the Israeli flag. Besides, I didn’t want to have a purple blog!

Inquiring minds wish to know.