white gold hardness

[digger]

I went to a jeweler this wkd, who asked me in what gold I''d like my rock set. I said 14K white, so that it would be a little stronger than 18k.

He proceeded to tell me that 18K white is harder than 14K white gold, and that it was opposite the trend to yellow gold. He said he wouldn''t set the stones in 14k white gold since it''s too soft.

Any comments as to whether or not this is correct?

 

[Shay37]

Hmmmmm, just a rookie, but am I the only one who smells fish?

Shay

 

[Shay37]

Okay, Digger, I am back. Sorry my answer was so flip, but I had to run an errand. The higher the percentage of gold, the softer it is. 18k is 75% pure gold. The other % are alloys of some type or another. 14k is somewhere in the neighborhood of 50% gold and the rest are alloys. I say neighborhood because these are ballpark estimates from what I remember of threads addressing alloys. Just on the percentages listed, I just refuted the jeweler's claim. However 18k is more expensive than 14k. How much, don't know. But that was what led to the fishy reference above.

I would do some more checking. Then I would decide how much I wanted to trust this jeweler with my ring.

Shay

Edited to make sense

 

[Brian Knox]

My goldsmiths confirm that 18KW is harder to work with compared to 14KW.

Yes, it sounds counterintuitive.

A long time ago I knew the answer why.

I believe that is is something to do with the atoms or molecules and how they line up at the molecular level.

Maybe a techie can chime with the details.

 

[Shay37]

Brian, does that mean that the metal is harder, or harder to work with, or is that the same thing? Either way, my bad. sorry.

Shay

 

[Garry H (Cut Nut)]

It all depends on his alloys.
If the white gold has nickel in it the more nickel the harder the metal.
If it has palladium added then it will be softer.

But hardness 2 things
1. = softness from wear - 10k scratches 14 scratches 18 etc
Add paladium and the white gold bends easier, takes longer to wear out but it scratches more easily.

2. = toughness from bending - 10k yG bends easier than 18yg but 14YG is the hardest to bend of all.

So it is not easy or simple and you need a metalugrist to explain about crystal structure and mixing issues etc as to why all these strange things happen.

 

[Brian Knox]

Hi Shay,

Actually , it was my bad ,in rereading my previous post, my answer was not clear.

For example: Platinum is softer than either 14KW or 18KW, but platinum is much "harder" to work with (more difficult to polish ,etc.)

Now back to the question of metal hardness.

It is my understanding that 18KWG has a higher hardness rating (harder)than 14KWG.

 

[Shay37]

Thank you, Garry and Brian. Wow, that really is a very complex issue. So, if I follow through with the thoughts, it would depend on what particular alloy was used; and each one changes the equation a bit. Thanks for the info, guys, good to know.

Shay

 

[Garry H (Cut Nut)]

and the karat is divided by 24 to get the %
14/24 = 58.5%
18/24 = 75%

 

[Brian Knox]

I wanted to second what Garry mentioned about 14KW palladium, and also mention that 14KW palladium is a very good choice for crowns ( second overall IMO to platinum)but there are actually times when 14KW palladium may be a better choice than platinum for crowns, such as in a design with "tall" prongs which in platinum would be more prone to bending than 14KW palladium.