Aluminum or Magnesium?

How can you tell the difference.
I`m pretty sure these are Alum.
Can Magnesium be polished?

 

those look aluminim.
magnesium can be polished,but it doesnt hold its luster as long as aluminum and they have more of a goldish tint to them.

 

Magnesium is visibly much more porous than aluminum plus it's way lighter.

 

Take something sharp and scratch the back side.If it leaves a mark and is soft its al --hard its mag---FEDER

 

Scratching probably is a good test, but I understand that scratches are stress risers and can lead to cracks in a true magnesium wheel.

 

Ummm...magnesium burns easily...got a lighter???

Just kidding...those look like aluminum "Petlichoff Wheels" (WAY inside there!) right outta the 70s to me.

 

American racing mags. Got a set on my coupe.

 

i was thinkin' along the same lines as hack. throw 'em on a fire. if they burn REALLY REALLY bright they were magnesium.

 

Clean off a little incon****uous spot and rub it with a vinegar-soaked Q-tip. If it bubbles, it is Mg...

 

i've never owned a real magnesium wheel, but it seems like the few i've picked up were REALLY light weight compared to other wheels, even aluminum ones. anyone confirm/disagree with this?

if i'm right about this and you take those tires off of them you should be able to tell just by picking them up.

 

Doesn't Mag kinda turn blackish fairly quick after rubbing.........

 

I`ve heard about the burning easily.
Dad told me a story about his firefighter days.
A VW caught fire and I guess the engine block was Magnesium and couldn`t be put out!!
Something about creating its own oxygen??

 

Mag tarnishes real easy. Polich a small spot in the back. Should tarnish within a few days

 

Those look just like my old American wheels, took off a 68 Corvette about 1975. Aluminum. Need a couple of skinny ones for front so I can use them on my coupe.

 

Magnesium is rather hard to ignite... You have to have a pile of shavings, or a really thin strip... Shower it with sparks, or some blowtorch love, and you'll have a white-hot flame temporarily blinding you...

It burns at 5400 degrees Farenheit (yeah, i'm serious)... It actually BURNS water, because the extreme heat causes it to seperate into Hydrogen and Oxygen, thus fueling the fire even more...

A thicker block of it won't burn...

 

We set off a trashed VW engine case in a fire ring at Huntington Beach on the state side. It was a ***** to get going but once it starte, it burned for quite a while. Had ppl coming all the way down Beach Blvd to see what it was.

 

if ya want to see magnesium burn just be at the bend in the road at bonneville on saturday night next year during speed week.

or go back and look at the bonneville pix that folks posted this year.

 

I have seen Magnesium Halibrands that were welded.
What is the trick so you dont lose your eyebrows doing that?
Is it no big deal or would you be taking a big risk?

 

Magnesium can be welded quite easy, but it has to be with TIG. The inert gas shields the oxygen away, and the temp is stillmuch lower than the ignition temp to make it burn.

 

No big deal than...Great!
What about the oxygen on the backside of the weld?
Thanks for the info 38.

 

I Welded magnesium once. I used a Gas trap on the backside of the Bead. definitely different, but not to difficult.