What's the significance of the colors of nuts

I don't see an unplated nut in the picture.
The one on the end has probably been in the sun more and is faded.

One is "gold" cad (cadmium) plated and one is "silver" cad plated. No difference. Info here: Cadmium.org

The plating thickness is extremely thin and both colors rust just as easily. Many steel parts are cad plated and it's not just used on fasteners.

We've got fasteners and other things cad plated under our TT and they are all rusting in just a year because our TT was exposed to lots of salt in the winter while being delivered to the west coast.

Cad plating is being phased out due to environmental concerns. Of course, not an issue for China. Not sure what they are using here in place of cadmium.

wa8yxm wrote:
This thread reminds me of a call to Tech Support at a company I know.. We need to replace a screw in our unit. We found the same size/rating screw at the hardware store but it is sliver not blue.

Customer Support response: The original screw was silver too before we painted it.

I don't know why, but that made me laugh pretty hard.

Bolts

For everything you ever wanted to know about bolts.

This thread reminds me of a call to Tech Support at a company I know.. We need to replace a screw in our unit. We found the same size/rating screw at the hardware store but it is sliver not blue.

Customer Support response: The original screw was silver too before we painted it.

The big box stores typically have grade 8 hardware plated the bronze color. While silver colored nuts can be standard or grade 5, the grade 5 fasteners are typically fine thread.

No one in the US plates with cadmium anymore due to EPA, unless it is for a very specific reason.

The silver nut is zinc plated steel while the bronze colored one is zinc plated steel with an iridite chrome coating which further enhances the corrosion resistance. Most automotive fasteners use this process.

Unless there are markings on the face of the nut indicating a grade 5 nut, it is a grade 2.

The "silver colored" nut might be zinc plated.
The "bronze colored" nut might be cadmium plated.
Then again, the silver colored nut may be grade 2 or 5, and the bronze colored nut may be grade 8.
Black anodized nuts are usually grade 2 or 5.
It all depends on the manufacturer.

The silver is an uncoated steel the gold is cadmium plated. There is no difference. What is the application? You need to use a nut that is equal in properties with the bolt or stud.
In other words do nut use a 2 or a 5 on a grade 8 bolt. Do not use aluminum on steel or vice versa.
Is this a shear application or a compression application. It all makes a difference.
Perhaps if you describe what you need to accomplish you would get a better answer. RV.net does not charge per word! go ahead free your mind,expand and expound on he subject at hand

westend wrote:
The colored nut has more alloy in it. It is formulated like that to prevent rust.

Does it matter if I use steel or its ok to use either one?