Rotary tumbling is one of the main ways people polish small to medium-sized stones. Vibratory tumbling is the main alternative, being quicker though initially more expensive. Rotary tumblers will smooth and round stones while a vibratory tumbler will polish them in their existing shape. See here and here for more detailed comparisons of the two methods. I use rotary tumble-polishers and have no experience with vibratory ones.
One of the reasons I started TumbleStone Blog in 2016 was the lack of New Zealand-based information on tumble-polishing and, in fact, the existence of very few practical and detailed online sources at all. I hoped to use my experiences to help other beginning tumble polishers.
In November 2017, I started a series of detailed and well-illustrated Posts on TumbleStone Blog called “The Seven Stages in Tumble Polishing Stones”. It went through, step-by-step, the various stages involved in collecting and polishing beach stones using a tumbler with a 4lb barrel. The first Post in the Series is here, while a summary can be found as #2 in “Six Past TumbleStone Posts of Interest to Beginning Tumble Polishers”. However, changes in late 2020 in the grits and polish stocked by my supplier mean that now only six stages are required instead of seven, and a couple of other minor changes have occurred. The original seven stages included: Stage 1 = Stone Collection (not usually included in accounts of tumble polishing); Stage 2 = tumbling in 100 mesh silicon carbide grit; Stage 3 = 220 silicon carbide grit; Stage 4 = 320 silicon carbide grit; Stage 5 = using a tin oxide “Pre-Polish” powder; Stage 6 = tin oxide “Pro-Polish” powder; Stage 7 = a “burnishing” tumble for a week in borax. The change to six stages is set out here.
A two-part series of TumbleStone Blog Posts that appears to have also proved useful for beginners is “What Do I Need to Start Tumble Polishing Stones Myself? And What Will It Cost Me?” Part One covers: The Tumbler; The Siting of the Tumbler; Silicon Carbide Grit; Grit Storage and Tablespoon Measuring; and Disposal of Slurry. Part Two covers: Tin Oxide Polish Powder; Polish Powder Storage and Mixing; Plastic Beads and Bead Storage; Soap for Cleaning and Burnishing; Sieves and Buckets; and Miscellaneous Useful Items. The original series was written in April 2018 but was up-dated in March 2022. Details about the changes requiring the up-dating can be found here.
Four other good New Zealand-based sources for tumble-polishing are the Facebook Group “New Zealand Lapidary, Rocks, Minerals, Fossils”, Nicola Gray, Chrissy Lampitt and Gordon Sherwood. More about these four below.
“New Zealand Lapidary, Rocks, Minerals, Fossils” is a “private group” on Facebook, meaning you need to join to see what is posted there and to contribute. The Group is described as follows: This group is for anyone interested in rockhounding, collecting or any of the rock Lapidary arts. It’s focus is on New Zealand material but anyone can contribute overseas material if you worked it here in New Zealand. Also any New Zealanders can contribute pictures of their rock collecting trips in New Zealand or abroad. Selling is not permitted on this forum. The Group was started in 2019 and in June 2022, when I first wrote this Page, it had 5,807 members, growing to 11,624 members in May 2025. It is very active, with daily postings and much interesting material. I have been a member since May 2020.
Nicola Gray, who lives in Hastings, Hawkes Bay, has a Facebook Page, New Zealand Rock Hound, My Rock Tumbling Journey, and a series of YouTube videos. Her posts and videos document many of the details of fossicking and tumble-polishing, as well as stone cutting. She simply states: I live in New Zealand. I love rock hunting, and especially love sharing my finds with others.
Chrissy Lampitt, from Papatotara, near Tuatapere on the south coast of the South Island, writes a regular blog called “Tumble and Polish”. She often fossicks at Gemstone Beach and polishes beach stones. She has both rotary and vibratory polishers. Her blog has lots of detailed Posts about her polishing, such as the series “How I Use my Lortone Tumblers (Step-By-Step)”. Chrissy’s practical advice is well worth knowing.
Gordon Sherwood’s “New Zealand Rocks Downunder” has a Facebook Blog and a series of YouTube videos. He introduces himself as follows: I live in the Bay of Plenty, a volcanic area so that means young rocks and have to travel to other areas for older rocks that contain interesting specimens. You can expect to accompany me as I find fossils, and uncover some of the interesting insect life here in New Zealand. Look out for my attempts at cutting and carving the rocks that I have found as I get the gear together to do it. I own a local retail business here in Kawerau that has been serving our local community since 2003… Our retail shop has a great selection of crystals and gemstones that fuels this passion to fossick. In May 2022, Gordon and his wife Beth relocated their shop to Edgecumbe.
Other Posts on TumbleStone Blog about tumble-polishing:
- “The Best Rock Tumbling Book Around – ‘Modern Rock Tumbling’ by Steve Hart (2008)” – I read this book early on in my tumbling career and found it directly relevant and immediately useful. It remains the best I have come across. It is available both as a “real” (paper) book and an e-book. April 2016.
- “Sources of Detailed Instructions for Tumble Polishing Stones” – A list of seven sources I have found useful for the beginning (and also for the not-so-novice) rock tumbler. They share a number of things in common but often have their own unique ideas or pieces of advice. April 2016.
- “How Stones Tumble in a Rotary Tumbler” – This video shows the tumbling action when a barrel is too full or not full enough. A great help in understanding why a barrel should not have too many stones in it! April 2016.
- “’It’s About Time!’ How Long Should I Leave My Stones Tumbling in a Barrel?” – May 2021.
- “Alternatives to Plastic Pellets as Tumbling Media: Reviewing the Advice – Part One” – September 2022. Part Two is still not complete.
- “Sunlight Soap, Borax and Tumble Polishing: Two Issues” – Using sunlight soap sometimes, though rarely, leaves a waxy lining on a tumbling barrel; and an additional use for borax, adding it to grit tumbles. July 2024.
- “How Much Does Tumbling Wear Away Trace Worm Cast Fossils?” – April 2020.
- “Six Newly Polished Stones from Kakanui: Close-Up Flaws” – A discussion of how smooth to make a stone with the grit stages before polishing it. August 2022.
HOME – FOSSICKING BEACHES – BEACH STONES – LIST OF CONTENTS TO DATE
Thanks so much for the mention! Your valuable blog posts are what helped me get started on my tumbling journey so I will always be forever grateful of what you share! I am even more grateful that we have become good friends and fossicking companions. Thank you for sharing your vast knowledge and expertise!