Pumpkin seed: Making a light lotion, Anamaria asked, I would like to know if I could ever make this same lotion adding magnesium chloride oil? Would it survive to the heat? Thanks
Magnesium oil isn't an oil. It's a solution of water and magnesium flakes, so it's a water soluble ingredient, not an oil. It could handle the heat well, so you could add it to the heated water phase of a lotion. Magnesium chloride is a salt or an electrolyte, and a lot of our ingredients really don't like electrolytes much, so check before you add it to your product.
The most common electrolyte we'll meet as bath and body makers is salt (external link), found as magnesium sulphate (Epsom salts), sodium chloride (table salt), dendritic salts (sodium chloride), and so on. (Magnesium chloride in magnesium oil is a salt.)
How much salt a product can handle will depend on the product. Surfactant blends like shampoo, body wash, or bubble bath can generally handle about 3% before they go really watery. (In fact, we can thicken some surfactant mixes with salt - it's called the salt curve.) Surfactants aren't a great place to use electrolytes.
Polawax is electrolyte tolerant, Natragem EW can handle up to 10% salt, but Aristoflex AVC will fall apart. Lotionpro 165 (aka Simulsol 165) is supposed to handle electrolytes well.
If you want to put it into a gel, check to see what you can use. Ultrez 20, my favourite carbomer, works very well with electrolytes, but if you use more than a titch, you'll start to lose viscosity. I'm working with Sepimax ZEN and Sepimax EMT 10 this week, two gel creating polymers that have good resistance to electrolytes, so those might work for a magnesium oil gel.
Xanthan gum is tolerant to high levels of electrolytes, and salts could actually help thicken it further. Guar gum is "uncommonly resistant" to electrolytes, and can be used in combination with xanthan gum to thicken it further.
If you want to use it in a product, try it at a low amount - let's say 3% - and see how it turns out. Make a small batch of the product to see what you think of it, and keep really good notes. Then add 1% every time you make it to see what you think. And come back to tell us what you think so we can share your experiences with other people who might like to make products with this magnesium oil.
A guide to magnesium oil
Magnesium picture above By Romain Behar, Public Domain