These tests will help you to determine the ratio of oil to water in a moisturising product.
Apply moisturiser to your skin. If the skin under the moisturiser is warm, there is a greater percentage of oil in the product. If the area is cool, there is a greater percentage of water. The science behind this is that evaporation cools, and water evaporates. Oil does not evaporate and therefore traps heat in the body.
Put a small amount of moisturiser on a tissue, and hold it over a lightbulb. Products with higher oil content will melt. The wider the area of melted oil, the greater the percentage of oil in the moisturiser.
I experimented this with Olay’s Complete UV Protection Moisture Lotion SPF15 for combination/oily skin.
So there you go, a useful beauty tip from the expert herself (I meant Bobbi 
).
Another method to check the oil-to-water ratio was a good tip I picked up from Traclyn, who ran an oiliness test of a BB cream on a piece of facial blotter. I think it is another good way to check if the product is going to be too greasy for you, especially if you suffer from oily skin.
Thirty-something. Gemini. Happily married. Loves shopping. Has an unhealthy adoration for bags and chocolate. Uses sunscreen religiously. Hates baked beans with a vengeance. Thinks that the weekdays should be a weekend long, vice versa. Optimistic. Narcissistic. Not the average Jane.
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{ 4 comments… read them below or add one }
the oil blotter test is rather accurate i would say. done them quite a while back just cuz i got too much facial blotters around!
i will try this bulb tip n see!
ahahah! fun stuff to do when i am not working!
this is a neat tip! my moisturizers are definitely higher in oil than water. well, I use both types!
I was just going to say I’m going to try this because I fear oil in all forms, but then I remembered my moisturizer is an oil free gel, because I’m so panicky about oil. Oops. blonde moment
Plue:
Haha, it’s a good experiment to try out. Just be careful not to burn your hand on the hot bulb, yeah?
Connie:
Thankfully, mine contains more water. Skin’s too oily to have it the other way round
Renee:
Hee hee! Nah, don’t worry about it, it happens to the best of us. I get my duh-brain moments too!