Jewelry metals

General Questions
#1

Can you look at a piece of shiny gray jewelry, and tell whether it is silver, platinum, or white gold? I sure can’t. I even have trouble telling between them and stainless steel, though the first ones tend to be on the dull side, while stainless is more mirror-like.

I know the reason is gonna have something to do with me being a guy, so I think it would be helpful if responses include your gender.

(No cheating. I’m referring to the appearance of the metal. Anyone who points out what “18K” or “.925” means will be shot.)

#2

If your intent is to save a couple of bucks and buy a cheaper metal then if it is for yourself, do it for your woman friend don’t.

I had a friend in High School who got the cheap metal they called lustrium. He told everyone it was platinum.

So, no I cannot tell the difference except for the price.

Jeffery

#3

I can, assuming the metallurgist is using the standard alloys. Silver is the whitest of those three metals, but dulls very quickly, and is so soft it soon picks up scratches. White gold has a tinge of yellow. Platinum looks grayer and duller than the rest. However…platinum and white gold are both commonly played with rhodium, a very shiny white sister-metal to platinum, so they can look exactly alike. Platinum settings tend to be more “solid-looking”, thicker shanks and prongs, but that is simply jewlery-making convention. If I am unsure whether something is white gold or platinum, I heft it; platinum is significantly heavier.

I am the daughter of a jeweler, and have worked in the buisness for about 8 years (not currently). I can also almost always tell on sight the difference between 10k, 14k, 18k, 22+k, gold plate and gold filled. We used to test gold with (IIRC) hydrocloric acid; you scratch the metal and drip some on. Green bubbles and smoke means goldplate or goldfilled. Dark discoloration means 10k. No reaction means 14k or above.

“Lustrium” was a variant of stainless steel. My class ring was in it too.

And do you really think this will spank a Great Debate? :wink:

“Eppur, si muove!” - Galileo Galilei

#4

It should be “plated with rhodium” above.

#5

…and “spark a great debate”. Sheesh. Must be time to go home.

#6

It does help to know the densities of the metals in question. Even if you can’t dunk a piece of suspect jewelry in a flask and measure its exact volume, you can still heft it in your hand to get a rough idea of how dense it is. In pure elemental form, here are the specific-gravities (densities in grams per cubic centimeter) of some common and jewelry metals:

<PRE>
zinc 7.14
iron (e.g. steel) 7.86
nickel 8.9
copper 8.96
silver 10.5
lead 11.4
gold 19.3
tungsten 19.3
platinum 21.4
</PRE>

Jewelry yellow gold is usually alloyed with zinc, while white gold is often 75% gold and 25% nickel.

Note that gold-plated steel would be very easy to tell from pure gold just by hefting it in your hand to feel the weight, but gold-plated tungsten would not, since tungsten and gold have damn near identical specific-gravities. So, the moral of this story is: If your going to buy your honey faux gold jewelry, be sure they use tungsten. :wink:

I’m not flying fast, just orbiting low.

#7

If Keeves buys her gold-plate she will spank him.

Jeffery

p.s. you are the daughter of a jewler and your class ring was lustrium?

#8

I am sensible enough to know that I wasn’t going to wear it all that much, so why waste the money? It was a HS ring, BTW; what sort of a dork would wear a “Kaneland High” ring once they’re out of high school? I’m not even sure anymore why I wanted one in the first place.

“Eppur, si muove!” - Galileo Galilei

#9

Ya know, I think Gaudere is right. For the first time ever, I’m moving a thread out of Great Debates and in to General Questions. (Gotta be fair – Nickrz throws plenty my way.)

David B, SDMB Great Debates Moderator

#10

Ok, I royally screwed that up. < sigh > Maybe this is why I don’t usually transfer stuff.

CKDextHavn: Can you please move this thread properly into General Questions? I tried to move the thread there AFTER I sent it here accidentally, and succeeded in moving a LOCKED thread there (if you can delete that version of this thread also, I’d appreciate it). If I do anything more, I’m just gonna screw it up more…

Sorry!

David B, SDMB Great Debates Moderator and Thread Mangler

#11

Silver tarnishes much more easily than either white gold or platinum. Just let the piece sit on your dresser for a few days. If it tarnishes, it’s silver.

My husband has a white gold engagement ring (yes, I gave him an engagement ring; why should I be the only one who gets to wear fancy jewelry?), and it has a gold cast to it in very bright light. Maybe it’s just that particular alloy, though. It’s nowhere near as white as platinum.

The Cat In The Hat

#12

Good work, David, and I’ll getcha for this.

OK, I am now moving this to General Questions where it belongs.

#13

Nothing is so smiple it can’t be screwed up.

#14

You other moderator guys are all wrong. This poster probably was referring to the mailbag I wrote about white gold: http://www.straightdope.com/mailbag/mwhtgold.html But this shows why it’s good for the OP to post a link to the column s/he’s referring to…
Jill
Feelings really, really hurt…

#15

Uh, Jill, if he was referring to it he probably didn’t know he was referring to it. I mean, certainly Keeves would never hurt your feelings!

#16

Everybody, make nice now. After all, that new alloy, Moderatorium, is just hitting the market. Won’t you be pleased to learn that Unca Cecil has ordered SD Staff rings for you all in it !!! ROFL

Typer

#17

Dex and David don’t get rings because they
planted a closed thread in my forum to make
me look bad. They get zinced sheeps.

#18

[[Uh, Jill, if he was referring to it he probably didn’t know he was referring to it. I mean, certainly Keeves would never hurt your feelings!]]
No, no, no. It’s you moderators who don’t read my mailbag columns!

#19

Nickrz: Don’t blame Dex for planting the closed thread in GQ – that was 100% me. (You could delete it though, you know.)

Jill: The moderators don’t need to read the mailbag – we already know everything (but you already knew that).

#20

Baseless allegations! I, for one, read the Mailbag on a regular basis, as I do all the forums (with certain exceptions). :wink: