How many oz is in each container?

1 Coarse-16oz. 2 Medium-13oz. 3 Pre-polish-12oz. 4 Polish-11.5 oz.

I just opened this and finished with grit one, went to put grit 2 in and bottle open and 1/2 full. How do I contact seller?

I would go through Amazon to get an answer for your problem.

Can it be used together ?

Each grit is a different fineness intended for a specific purpose. We do not recommend using them at the same time. We do recommend 1 TBS grit per per 1 LB rocks, at each cycle. For further information please contact us at help@natgeotoys.com.

After each step for the rocks in the kit, my rocks dry with a dull white finish. It doesn't show when it is wet. Am I doing something wrong?

No. I find that after tumbling with the finest grit after the last step... and thoroughly allowing the rocks to dry, a nice coat of wax or oil brings out the color beautifully.

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NATIONAL GEOGRAPHIC Rock Tumbler Grit and Polish Refill Kit - Tumbling Grit Media, Polish Up to 20 lbs. of Rocks, Works with any Rock Polisher & Tumbler Supplies

Product ID: 37710951

📦wide-mouth, secure storage containers

🪨polishes up to 20 lbs. of rocks

⚙️4-stage precision grit system

50143CFA

Duties & taxes included

In stock

Sold byAmazon SenegalDelivered byDesertcartCustomer service byDesertcartReturns14 days · 30 with PRO

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Description

🪨 Transform your stones, transform your space — polish like a pro!

BULK POLISH POWER - Refill kit handles up to 20 lbs. of stones—perfect for serious hobbyists and pros alike.
AWARD WINNING QUALITY - Backed by Blue Marble’s Toy of the Year-winning innovation and U.S.-based support.
EFFORTLESS ORGANIZATION - Wide-mouth, screw-top containers keep grit fresh and measurement simple.
UNIVERSAL COMPATIBILITY - Works seamlessly with all rock tumblers, maximizing your existing setup.
4 STAGE TUMBLING MASTERY - From rough shaping to mirror polish, every step engineered for flawless results.

The NATIONAL GEOGRAPHIC Rock Tumbler Grit and Polish Refill Kit offers a premium 4-stage silicon carbide grit system designed to polish up to 20 lbs. of rocks, gems, and glass. Compatible with all tumblers, it comes in easy-to-use wide-mouth containers and includes a grit scoop and instructions. Trusted by STEM enthusiasts and backed by award-winning Blue Marble, this kit elevates your rock tumbling experience with professional-grade results.

Specifications

ASIN	B01MRKI4W0
Age Range Description	14 years and up
Best Sellers Rank	#1,744 in Industrial & Scientific ( See Top 100 in Industrial & Scientific ) #1 in Tumbling Media
Brand Name	Blue Marble
Color	Black
Customer Reviews	4.7 4.7 out of 5 stars (14,258)
Educational Objective	STEM
Global Trade Identification Number	00816448020636
Included Components	4 Stages of Rock Polishing Grit, 10 mL Grit Scoop, Rock Tumbling Instructions
Item Dimensions	5.5 x 5.5 x 4.25 inches
Item Type Name	Rock Polishing Grit Media
Item Weight	1.78 kg
Manufacturer	JMW Sales, Inc.
Manufacturer Maximum Age (MONTHS)	1188
Manufacturer Minimum Age (MONTHS)	168
Manufacturer Part Number	NGBULKGRIT
Manufacturer Warranty Description	We're proud to make the highest quality products which are backed by exceptional service.
Material Type	Silicone
Model Number	NGBULKGRIT
Number of Packs	4
Number of Players	1
Operation Mode	Manual
Set Name	Rock Tumbler Grit Refill Kit
Size	One Size
Sub Brand	NATIONAL GEOGRAPHIC
Supported Battery Types	No batteries required
Theme	Rock Tumbling
UPC	816448020636
Unit Count	1 Count

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