Rock Tumbling

Many thanks to Karla for sending me a copy of this newsletter from The Rock Seeker. She thought it might be perfect for my blog.

Did you know that rock tumbling isn’t just a thing we do here on Earth in our garages or sheds? It’s actually happening right now in outer space as well. Micrometeorites and cosmic dust are constantly colliding with asteroids, which gradually wears down and smooths their surfaces over millions of years. This natural “tumbling” process can create surprisingly polished surfaces on these rocks that are hurling through space. As a matter of fact, many of the meteorites that have fallen to Earth have gone through this cosmic polishing, making them the ultimate polished stone!

​Here’s what’s in today’s newsletter:

• In The Spotlight – Tumbling 101
• Tip of The Day – What to do with all that grit?
• Video of The Day – Cutting lightning stones
• Quiz of The Day –Tumbling and a review question
• Picture of The Day –It looks cold, but I’m still going in!

IN THE SPOTLIGHT​

​Rock Tumbling 101: A Beginner’s Guide to Polishing Stones to Perfection​

Rock tumbling has been around forever. Ok, maybe not forever, but for a very, very long time…essentially since the beginning of civilization. Of course it’s evolved over that time, as have many aspects of lapidary, but it’s still about taking ordinary stones and finding the beauty that’s hidden just beneath the surface.​

For me, rock tumbling is more than just a hobby; it’s my happy place. There’s something incredibly soothing about the steady hum of the tumblers. And of course the thrill of seeing rough stones transformed into polished , and the pure joy of holding that final, polished piece in my hand, is an experience that never gets old. It’s a little bit of magic in every tumble.

​Read The Guide

TIP OF THE DAY​

What To Do With Used Rock Tumbler Slurry?

Never pour rock tumbler slurry down the sink drain. The fine grit and rock particles can settle and harden, into a concrete-like substance and create serious clogs in your plumbing. Instead, pour it out in your gravel driveway or even in your yard. Don’t have a yard or gravel driveway? Check out these other tips on how to dispose of tumbler slurry.

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VIDEO OF THE DAY

​If you love septarian nodules (lightning stones) and you also enjoy watching rocks being cut open, then this video is a must. Join Tayler, from Agate Dad, for an exciting day of cutting open rocks to see what’s hidden inside. In this episode, he’s tackling lightning stones and shares his simple technique in case you want to start cutting open your own.

​Cutting Open Lightning Stones (Septarian Nodules) To See What’s Inside!​​Agate Dad/YouTube​

What Are Septarian Nodules?Septarian nodules are fascinating, naturally occurring geological formations that are highly prized by collectors for their unique appearance and composition. These nodules, or “septaria” (from the Latin word “septum” meaning partition), are typically round or oval-shaped stones that have a cracked interior filled with minerals like calcite and aragonite, which form beautiful, angular cavities or “septae.”​Septarian nodules originated as mud balls that dried and cracked as they shrank. Over millennia, these cracks were filled by percolating mineral-rich liquids that precipitated to form the crystalline structures seen in the cavities. The most common minerals filling these cavities are yellow calcite, which forms the bright, eye-catching centers, and brown aragonite, which usually forms the outer layer. Other minerals like quartz or pyrite may also be present, adding to the nodule’s aesthetic and scientific interest.​The external shell of septarian nodules is typically composed of a grey limestone or bentonite clay, which provides a stark contrast to the vividly patterned and colored interior. The combination of these elements makes each nodule uniquely picturesque.​Learn More About Septarian Nodules

QUIZ OF THE DAY

​1. Which of the following is not a recommended type of rock for tumbling?

A) Jasper

B) Agate

C) Soapstone

D) Chalcedony

​Check Your Answer ​

​2. In yesterday’s newsletter we talked about “asterism” and star sapphires. What are the inclusion that creates the asterism effect in star sapphires?

A. Hematite
B. Rutile
C. Calcite
D. Pyrite

​Check Your Answer 

PICTURE OF THE DAY

​Lake Superior on a calm day.  Looks cold, but that won’t stop me!

Sovereign Photography/IG