Intro: Lead Tree
This is an instructable on growing the lead tree, arbor Saturnus.
It is a crystalline formation of metallic lead, in this case forming the leaves of a wire tree. Micheal Faraday made a passing reference to one in The Forces of Matter while giving demonstrations on the relationship of chemistry and electricity. A short description on the preparation of a lead tree was included in a footnote, although he didn't give any indication of what it looked like. I couldn't find anything on the internet either so the only way to find out was to try it.
Step 1: Materials
- Lead Acetate
- lead (fishing sinkers)
- distilled vinegar
- hydrogen peroxide
- Zinc (from battery)
- Brass wire or tree
- Clear nail polish (optional)
- Clear jar or container to fit tree
- Rubber gloves
I followed this instructable to make the tree. If you don't want to take the time to make on you can just twist a bundle of brass wires at one end and bend them out in a kind of cone.
Here is an instructable for getting zinc from the battery.
Step 2: Lead Acetate
I was surprised not to find an instructable for this.
Wear rubber gloves for this step. Take great care not to come into contact with the lead or lead acetate.
Fill a container about half full with household vinegar, and the rest with hydrogen peroxide. Place some lead inside and cover the container. Bubbles should start forming around the lead. I used muzzle loader balls for this but fishing sinkers should work fine. In my first attempt I used lead recovered from a car battery, but battery lead isn't pure and I could only get very small crystals to form using it.
I used about 1.25 ounces of lead in a quart of fluid. It will take some time for the lead to dissolve. Hammering the lead flat will increase the surface area and speed the process up, so will heating the mixture. I left mine on a candle warmer for a couple days.
When most of the lead is dissolved and the bubbling has stopped pour the lead acetate off of the remainder. There may be a fine white powder left in the bottom. My best guess is that this is lead chloride from something in the vinegar.
Step 3: Brass Tree
Flatten the zinc and mount the tree on it. Be careful to keep the zinc and the tree clean. Bend the "roots" over to make a good connection to the zinc and keep the tree stable.
When the tree is mounted you may want to coat the trunk and the base of the roots with nail polish to prevent leaves from growing there. After it is dry carefully place the tree in the container.
Step 4: Add the Lead Acetate
Pour the lead acetate over the tree. Fill the container completely and cover with a tight fitting lid. Again wear gloves and be careful not to spill any of the lead acetate.
Step 5: Growing
Since the zinc has a higher electronegativity than lead,
it will substitute in the lead acetate giving zinc acetate and metallic lead which will crystallize on the zinc. The brass and zinc together form a kind of battery which attracts some of the lead to crystallize on the brass. Copper will work also, but it takes much longer.
Lead will begin to deposit on the zinc immediately, and leaves should start growing in about an hour. The tree will continue to grow until either the lead or the zinc is exhausted.
Thank you for reading!