Copper, silver, or gold MC cartridge coils?

Copper coils seem to be the most popular.

Silver coils seem to have the general trait of warmer midrange and extended high frequencies, by those that prefer them.

Copper has lower mass than silver, and much less mass than gold. Better transients?

Silver has the best conductivity, followed by copper, then gold.  Gold has the best corrosion durability.

Can we draw any conclusions as to the type of sonic traits and preference of each type?

Any preferences and why your choice of type, or is there no big differences sonic wise?
Dear friends : In the long MM thread J.Carr touted a lot the Sony LOMC cartridges and especially the 55/88 top of the line and he did it because not the coils wire type but because its unique coils wiring shape:

""  The Figure 8 coil was meant to address to recurrent problems of moving-coil : low output, field-disturbing iron core, and increase of coil turns to increase output.

By giving one part of the armature a 90° twist, the two halves of the coil do not cancel each other out but produce voltage with both inward and outward movements.
No need to use a stronger iron core or increase the number of coil turns : linearity is improved, the cantilever isn't burdened by a heavier coil and output is doubled - simple. ""

So, exist several cartridge design characteristuics more imporant for the designers than the coil wire types that's important but with a different priority level in the cartridge designs. On Dynavector site you can read:

"""  At a glance, the XV-1 is different from all cartridges that have gone before. Its magnetic circuit comprises 8 small ALNICO magnets. The magnetic path is divided into two - In the magnetic gap, a specially designed magnetic flux equalizing piece is placed. On the front yokes, magnetic stabilizing coils are wound. By this special combination, the magnetic field becomes widely homogeneous and more linear than the conventional magnetic design that is common in existing MC cartridges. Currently the design trend of MC cartridges is to employ stronger and harder magnets. The XV-1 takes the opposite approach. This is the theoretical conclusion of Dynavector.  ""

Ortofon or Allaerts and other top manufacturers took special attention on several other cartridge design characteristics as with Ortophon is legendary Ortophase pattent.

Again and as @lewm  confirmed : ""  it is the overall design that counts far more. ""

The explanation about the Sony came from a site that reviewed item not from JC.

I have just broken in my ZYX airy 3 SB gold cil cartridge after 30 hours of use and it sounds great.

Better than the Silver coil and Copper versions IMO.

I use a VPI TNT 3 Special turntable with JMW 10 arm from 1990.

ARC used the same turntable as their reference from 1990 until 2020 in their factory.

I have identical JMW10 arms and use the copper coil and silver coil versions for comparison.

Doug Deacon the SoraSound reviewer, had the wrong opinion of these variations.

He said the gold version was a cream puff in sound and was totally wrong.

He liked the copper best and thought the silver had poorer transients.

Not IMO!

The Gold is best followed by silver and copper coils.

SoraSsound  had a big stock of copper coils and a few silver and very few gold coils.

SoraSound did not want to run out of copper or silver, if the demand was bigger for silver or gold IMO

A business decision on SoraSound's part, to maximize profit.

This opinion is sort of mute because the Airy 3 with boron cantilever is long gone.

You have to try for yourself,, and not believe the paid SoraSound shill reviewer Doug Deacon, who is long gone.

There are many shills on the internet that try to influence the public and act as independent reviewers. 

You stated that the silver wired Zyx has 3 years usage, and the copper wired Zyx has 1.5 years use.You stated that the Gold wired Zyx is new.
Therefore the comparison is irrelevant and your conclusion flawed.

Furthermore, I would wager that if you compared two cartridges with the same wire - they will sound different.

I use stylist and all the cartridges are is great shape!

I get 3000 hours of life with stylast , and there are many audiophiles agree with the life of my cartridges.

You do not know what you are talking about IMO.

I know what these cartridges sounded like over their usefull life.

Why would two identical cartridges sound different?

 ZYZ makes quality cartridges that have very little unit to unit sonic variation.