Yesterday, Saturday January 8, 2011, I started my first Lava Lamp Project (using an old Lava Lamp I had laying around). I found a formula at:
I followed the instruction as close as I could with my limited jars/scales etc. to try to be as accurate as possible. More on that later.
I just wanted to comment quickly (er...) on a cool phenomenon I noticed while I was adding salt to the water to get the right density, which I failed to think to take a picture of.
I knew the salt might end up underneath the ooze and tried to mix/tip the glass as I was going. I was probably adding salt too quickly as I am impatient. I initially added the recommended 1 tsp. and let it sit for a while (10 minutes). I then started adding 1/4 tsp. at 5 minute intervals or so while gently stirring with a 1/4" titanium rod I had laying around.
One of three things would happen as I added the salt.
1. It would dissolve before hitting the ooze at the bottom.
2. It would spread out radially over the dome of ooze and drop further between the glass and the ooze to settle beneath the ooze.
3. If way too much salt was added too quickly it would funnel through the middle of the ooze to the bottom. Nifty.
So thinking I had everything under control, I kept adding 1/4 tsps. of salt and gently stirring and tipping the glass to make sure things were mixing properly and keeping an eye on the dome. Well, I think I slacked up a bit on the mixing (which I was doing over the lamp base to try to maintain a semi-steady state system. It seemed like the dome was rising but would not lift off.
I picked up the glass for further inspection to find that a third layer had appeared at the very bottom! There were no salt grains, but clearly this was a high density water layer. Cool! Here is where I should have snapped a few pics. ;-(. So I had three very distinct layers going on, the top low density water, the ooze and then the high density water on the bottom (maybe a 1/2" worth). So after staring at it in amazement (I'm fascinated by small shiny objects too.) for about 10 minutes, I decided it was time to mix it up. I didn't want to shake or stir it violently for fear of emulsification. So I took to tipping the glass back and forth. I could not get the high density water to mix with the low density water. You could clearly see the different densities and heat waves with the refraction of light. As I tipped the glass, the ooze would still "seal" the two water layers from each other. I started trying to get some dynamic wave action going to get the two to mix, even when the ooze layer appeared to allow the two layers of water to come in contact with each other I was have a very hard time getting them to mix. Long story short (haha) I eventually got two layers of water to mix and I now have a single density water solution, whew! And despite adding approximately 5 tsp. of salt, I think I am very close to having it right. This morning (Sunday January 9, 2011 around 8:00AM the ooze had seemed to be mostly settled near the bottom. I am currently trying to tweak it to get it right. I am afraid to add more dish soap as the current dynamics are pretty cool.