Sylvia,
 
My landlord is one of the people who helped develop WD-40 here in San 
Diego during WWII.  I'll see what information I can get from him 
concerning its content.
 
Best regards,
 
Kim Hutsell
Field Research, Marine Malacology
San Diego
 
 
Sylvia in Alabama wrote:
> 
> I have a question and an old issue to rehash.
> 
> Question:  to those in Florida's "fire zone" which direction is the wind
> blowing today?  (I want to know about the smoke in the Panhandle, if it
> is coming from the southeast).
> 
> Old Issue:  I am still a staunch believer in WD-40 for shells.  Someone
> shot me down, saying it was a petroleum product and would eventually
> cause the shells to yellow.  How do you know it is a petroleum product?
> It doesn't say so on the can.  I was always under the impression (and
> still am) that is it silicone, a combination of the element silicon and
> oxygen, and a carrier to make it into a spray-on form.
> 
> If it is a petroleum product, then why would it yellow and not the
> petroleum products cited to use, such as mineral and baby oils?  Why
> doesn't lighter fluid (another petroleum product) cause them to yellow?
> 
> I started using WD-40 15-20 years ago, when I first heard about silicone
> oil and it wasn't readily available.  I have not seen it adversely
> affect my shells in any manner.
> 
> When silicone oil became available I tried both, have both, and prefer
> the WD-40 because it dries faster and is easier to use when you have
> only one shell to do.  I've never had to redo a shell I've done with
> WD-40.  Dust, smoke, and grime do not stick to it.  I can dust the
> shells with my hair dryer if I prefer.  Once or twice, I have rinsed
> them under cool water and wiped them dry, but couldn't tell that it made
> a difference.
> 
> And - what is silicon oil (see my dictionary definitions below)?  Isn't
> it a compound of the element silicon, and some kind of oil?  What
> amorphous states other than crystalline does silicon occur?  What oil?
> Is the oil not petroleum based?  Is it vegetable based? Or is it pure
> silicon liquefied under heat or pressure?
> 
> OK, all you Ph.D's, chemistry majors, and museum curators:  Tell me why
> I'm wrong, not just that WD-40 shouldn't be used because it is a
> petroleum by-product.  Prove to me that it is, and prove to me that
> silicone oil isn't.
> 
> Sylvia Edwards
> Huntsville, AL
> -----------------------
> sil·i·cone, n. Chem.
> any of a number of polymers containing alternate silicon and oxygen
> atoms, as (–Si–O–Si–O–)n, whose properties are determined by the organic
> groups attached to the silicon atoms, and that are fluid, resinous,
> rubbery, extremely stable in high temperatures, and water-repellent:
> used as adhesives, lubricants, and hydraulic oils and in electrical
> insulation, cosmetics, etc.
> 
> sil·i·con, n. Chem.
> a nonmetallic element, having amorphous and crystalline forms, occurring
> in a combined state in minerals and rocks and constituting more than one
> fourth of the earth's crust: used in steelmaking, alloys, etc. Symbol:
> Si; at. wt.: 28.086; at. no.: 14; sp. gr.: 2.4 at 20°C.