During one of my time travels, I met this Shaman. It was in year 2400 AC, if I remember well. Humanity has been almost destroyed and technology returned to stone age. Remains of former technology were worshiped as powerful artifacts. This necklace is a reproduction of the one this techno-shaman (as she called herself) wore.

Apologies

As English is not my mother language, and as it is difficult to find technical terms translations, I hope that I this Instructable will be understandable but don't hesitate to tell me in comments if any term or sentence is not clear enough. I'll correct as soon as possible.

Step 1: Tools and Materials

As I wanted this necklace to look like it has been made without any advanced technology and tools, I chose to use only basic technics, tools and materials.

Materials

thin leather skin (1mm thin)
leather lace
electronic and computer components such as
- 3 old microprocessors (2 Intel and 1 AMD).
- 1 diode and its heat sink
- many resistors
- contacts
leather eyelets
leather rivets (sort of eyelets with a soft nail you can crush inside).
jewelry rings
fishing thread (not pictured)
magnetic necklace clasp
Green glass paint (not pictured)

Tools

cutter,
pliers
ruler, square
a pencil that can draw on leather
presses
neoprene glue
awl
cutting pliers
leather hole punch
driller

Step 2: Central Part

The central part of this necklace is mainly composed from three old microprocessors stuck in a "sandwich" of leather.

Notes

At first, I was planning to hang this part to the lace with leather loops. That's why leather front part is bigger than back part. I changed my mind afterwards so don't care these size differences due to loops that I finally cut.
It could be better to cut back and front leather parts a little wider than needed to re-cut both layers after they are glued together to have better looking edges.

Pics 1 and 2

As the microprocessors are 5cm x 5cm squares, I cut the back and front part 6cm width (5mm margin left and right) x 21cm long (1cm between each microprocessor and 5mm margin top and bottom).

In the front part, I cut 3 squares that are 4.7cm x4.7cm (there's a 1.5mm margin between the edges of the microprocessors and the beginning of their pins)

pics 3 and 4

Neoprene glue has been put on microprocessors edges and front part holes circumference. Remember that this king of glue is a contact glue : let it dry on both surface before putting them on together. Let microprocessors pins jut out above leather surface.

pics 4,5,6 and 7

As center microprocessor (an AMD) is a little too "nude" to my mind, I decided to add a diode and its heat sink on it. I drilled 3 holes on the center corresponding to the 3 pins of the diode. These pins were twisted behind the processor surface to be sure diode wont move.

pics 8 and 9

Back leather part and front leather part (including microprocessors backs) are covered with neoprene glue and, once the glue is dry, stuck together using presses.

Step 3: Side Parts

Depending on the resistors I have chosen, I draw a pattern for the side parts that take in account the number and the length or resistors I wanted to use (pic 3)

pics 1 and 2

First draw the shape of the pattern 4 times on leather back 2 using recto of pattern, 2 using verso. Cut these parts using a cutter.

pics 3 and 4

Using resistors positions drawn on pattern, drill small holes using an awl in two of the parts. Beware : use the verso of pattern for the first part and verso for the other.

pics 5, 6 and 7

Pass resistors pins through the holes and use a cutter blade to bend them behind the leather without folding it.

Line up the 2 pins of same resistor and cut them using the same cut.

pics 8 and 9

Make a spiral of neoprene glue on the front and back of a side, wait the glue to dry and use the press to glue it in place.

Step 4: Linking Parts Together

Now that we have our 3 parts (pic 1) let's link them together. Again, post apocalypse / techno shaman view will be the goal so electronic parts will be used.

pics 2 and 3

Use leather hole punch to make holes at approximately at 5mm of edges :

for central part : on top corners and in the gaps between the microprocessors.
for side parts : in every corners.

Stick contacts in the female part of the rivet (the one with the head), put this part in the hole and, using pliers, press firmly the male part into it. Warning : To avoid scratching rivet head with pliers, put a cardboard part (or a leather remain) between rivet head and pliers before pressing.

Depending on holes, there will be one or two contacts :

for central part : 2 contacts for 4 topmost rivets, 1 contact for 2 bottommost rivets
for side parts : 2 contacts for the corner at the intersection of the straights borders, 1 in the others.

pic 4

To fill the gap between the microprocessors and to visually link center and side parts, same resistors as side parts have been used.

Bend resistors pins to the same length than the gap between the two contacts holes. Then pass the pins in the holes and bend them behind.

pics 5 and 6

To link the parts together, smaller resistors have been used. Use round jaws pliers to make a loop inside contact holes with the resistor pins.

Now, only topmost contact holes are free. They'll be used to hang these parts to the lace.

Step 5: Lacing and Hanging

The necklace will be hanged to a leather laces plait.

pic 1

Put a jewelry ring in one part of the magnetic necklace clasp hole. pass one leather lace inside this rig to make a loop glue the two side and the glue another lace on them.

pic 2

To hide the gluing and strengthen it, I used an archery technic that is used to make bow strings. Note that colors are used to make scheme easier to understand but different color doesn't always mean different thread.

Put a fishing thread along the laces. Roll it around the laces and itself starting rolling at 2/3mm of lace loop.
After at least 10 turns around the lace, cut the starting of the fishing thread.
Put another fishing thread loop along the laces with its loop backward the laces loop (blue line on scheme)
Continue rolling the first thread for at least 10 other turns around the laces and the other thread and put its end inside the "blue thread" loop.
Pull firmly on the "blue thread" to get rolled thread under the rolls already made. Rolled thread end will get out at the middle of the roll. Cut it and use a lighter to melt the remain.

You can see the results in pic 4.

Not pictured

Make a plait with the laces. If you don't know how to make a plait, you can check here for example : https://www.instructables.com/id/How-to-Make-a-Fis...

pic 3

When the plait has the correct length (40cm in my case), do the following :

separate the 3 laces.
cut 2 of them at the final length minus 2 or 3 mm.
cut the other to make a loop.
glue the 3 laces and use the same technic described in pic 2 to cover gluing with fishing thread.