Mystery Yarn Sparks Weaving Mojo.

My mom has lots of yarn, notions and material, as she was digging around her magic closet, she came across two cones of this. The story behind the yarn, well, we owned a grocery store with a cafeteria and we were close to the Miami River's shipping docks for freight cargo back in the late 70's early 80's. The men that traveled the cargo ships would come in, buy supplies and eat the great Cuban food my mom's cook Ana would make, in those trips they noticed that my mom and grandma, who both worked in the store and cafeteria would knit at idle times. As thank you gifts they brought them these cones of hilo(thread) pronounced [eelo] in Spanish. My grandma crocheted me a dress for my 18th birthday in a royal blue(azul vitral) [asool veetral] which I have to this day, I must get it out and take a pic of it. The colors were always primary; red, green, white and royal blue, I never saw yellow or black. They came from Santo Domingo (Dominican Republic), Las Islas ( the Islands) or Centro America (Central America) somewhere on the southeastern coast of the Caribbean. It's not much to go on but that's their history, they are at least 20 yrs old and from the Caribbean - mysterious? Maybe, maybe not. What is it really, I don't know, I assume it's cotton crochet yarn because that what my mom and g- ma used it for, so I compared it with what I have on hand.

#1 - is the mystery yarn it is 3 ply I think cotton with very thin tight twist 2.75mm or 2.25mm

#2 - is Aunt Lydia's size 3 100% mercerized cotton also 3 ply - 3.5mm needles

#3 - is Bernat Cool crochet 70% cotton 30% nylon 6 ply cabled - 3.75mm needles

#4 - is Peaches and Creme 100% cotton 4 ply ww - 6mm needles

I still don't know how to figure out the scale of measuring yarn, that more experienced weavers use to identify yarns, like(80/20 or 80/10), I have read it a few times but it hasn't really sunk in. Since I'm visual I need to see the difference to really understand what is being talked about. A trip to the local LYS might help, and that is on my to-do list. I also don't know how to do the burn test I heard of other folks doing and quite frankly scares me some.

Here they are in the order that I photographed the threads, except for the cabled crochet. I did notice that the mystery cone has a super high sheen and doesn't break if I pull on it really tight, I can can break the Aunt Lydias and the Peaches. It is also the thinnest yarn I've ever thought about working with and the cone is plastic PVC. The mystery yarn has sparked my imagination for some weaving, I'm planning a shawl with it as warp and weft since I think it will drape really nicely and I want to see what it does together. Then I plan to try some experiments with the different yarns to see how they all react to each other after weaving, washing and drying. My Weaving Mojo is back and in force, this should be fun.

If anyone has ever seen any yarn that looks like this and knows what it is please let me know.