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I stay away from Vaseline, I find it to thick and it is too hard to clean off afterwards.

As far as its use with silicone, I am 98% sure it would be fine. "Natural" oil based lubes are suitable for silicone, think of silicone bake-ware use for cooking. Vaseline is a petroleum base, so that is why I am not 100% sure.

That being said, I am currently testing this kind of thing. Have done my silicone lubes and oil based (Natural) lube testing, my next test will be with petroleum based oil lube. I will be sure to let you, and everyone else know my results in an upcoming Workshop right here on the forums.

If you can not wait that long, try a small bit on the base of the toy. Let it sit there for an hour and clean off.

Since vaseline is oil based, it shouldn't affect your silicone toys. However, I'd do as Dwtim suggested and test a small amount on the base of the toy. Try rubbing it in, too.

Toytime is good with the info.

Vaseline won't ruin your silicone toys, but it doesn't lube well and is too thick to be very effective. ToyTimeTim is also right about it being hard to clean off.

Water based lubes aren't very expensive and work well for almost any sex use, and commercial oil lubes can also be a good choice for silicone. If you want to use something that's "homemade" try mixing some Crisco with melted coconut oil - it's thin enough to work well as a lube when it warms up to body temperature.