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Kona Dolomite (KONA32)
Notes specific to this specimen: We cut and polish these particular Kona Dolomite pieces to showcase the uniqueness of this material. Here the front is cut and polished. It sits upright on a flat base with a slight angle for optimal viewing. The back is left rough.  This piece has beautiful coloration.Great conversation piece of one of the world’s oldest fossils.
SIZE: 3″ HighNAME: Collenia kona
AGE: Paleoproterozoic Era 2.3 billion years
UNIT: Kona Formation
SITE: Kona Hills, Michigan
DATE: 2025
BY: Jon Kramer & Julie MartinezDocumentation: This authentic fossil specimen comes with a Certificate of Authenticity and Origin. In addition, an attractive and informative display card accompanies the specimen.
$65.00Kona Dolomite (KONA32)
$65.00 -
Kona Dolomite (KONA33)
Notes specific to this specimen: We cut and polish these particular Kona Dolomite pieces to showcase the uniqueness of this material. Here the front is cut and polished. It sits upright on a flat base with a slight angle for optimal viewing. The back is left rough.  This piece has beautiful coloration.Great conversation piece of one of the world’s oldest fossils.
SIZE: 3″ HighNAME: Collenia kona
AGE: Paleoproterozoic Era 2.3 billion years
UNIT: Kona Formation
SITE: Kona Hills, Michigan
DATE: 2025
BY: Jon Kramer & Julie MartinezDocumentation: This authentic fossil specimen comes with a Certificate of Authenticity and Origin. In addition, an attractive and informative display card accompanies the specimen.
$85.00Kona Dolomite (KONA33)
$85.00 -
Kona Dolomite (KONA34)
Notes specific to this specimen: We cut and polish these particular Kona Dolomite pieces to showcase the uniqueness of this material. Here the front is cut and polished. It sits upright on a flat base with a slight angle for optimal viewing. The back is left rough.  This piece has beautiful coloration.Great conversation piece of one of the world’s oldest fossils.
SIZE: 3″ High
NAME: Collenia kona
AGE: Paleoproterozoic Era 2.3 billion years
UNIT: Kona Formation
SITE: Kona Hills, Michigan
DATE: 2025
BY: Jon Kramer & Julie MartinezDocumentation: This authentic fossil specimen comes with a Certificate of Authenticity and Origin. In addition, an attractive and informative display card accompanies the specimen.
$75.00Kona Dolomite (KONA34)
$75.00 -
Kona Dolomite (KONA35)
Notes specific to this specimen: We cut and polish these particular Kona Dolomite pieces to showcase the uniqueness of this material. Here the front is cut and polished. It sits upright on a flat base with a slight angle for optimal viewing. The back is left rough.  This piece has beautiful coloration.Great conversation piece of one of the world’s oldest fossils.
SIZE: 3″ High
NAME: Collenia kona
AGE: Paleoproterozoic Era 2.3 billion years
UNIT: Kona Formation
SITE: Kona Hills, Michigan
DATE: 2025
BY: Jon Kramer & Julie MartinezDocumentation: This authentic fossil specimen comes with a Certificate of Authenticity and Origin. In addition, an attractive and informative display card accompanies the specimen.
$65.00Kona Dolomite (KONA35)
$65.00 -
Kona Dolomite (KONA36)
Notes specific to this specimen: We cut and polish these particular Kona Dolomite pieces to showcase the uniqueness of this material. Here the front is cut and polished. It sits upright on a flat base with a slight angle for optimal viewing. The back is left rough. Superb banding from the stromatolitic layers. Great conversation piece of one of the world’s oldest fossils.
SIZE: 5″ Long
NAME: Collenia kona
AGE: Paleoproterozoic Era 2.3 billion years
UNIT: Kona Formation
SITE: Kona Hills, Michigan
DATE: 2025
BY: Jon Kramer & Julie MartinezDocumentation: This authentic fossil specimen comes with a Certificate of Authenticity and Origin. In addition, an attractive and informative display card accompanies the specimen.
$85.00Kona Dolomite (KONA36)
$85.00 -
Kona Dolomite (KONA9)
Notes specific to this specimen: This is an excellent sliced section showing multiple stromatolite colonies with distinct layers (laminae). The clear layering is unusual for this slightly metamorphosed material. It has a smooth back and a flat bottom so it stands up nicely.
SIZE: 6″ x 3″ x 1″
NAME: Collenia kona
AGE: Paleoproterozoic Era 2.3 billion years
UNIT: Kona Formation
SITE: Kona Hills, Michigan
DATE: 2023Documentation: This authentic fossil specimen comes with a Certificate of Authenticity and Origin. In addition, an attractive and informative display card accompanies the specimen.
$245.00Kona Dolomite (KONA9)
$245.00 -
Potomac Marble Sculpture
Notes specific to this specimen: You won’t find this on the market anywhere! Why? Because we are the only people who excavate and sculpt this beautiful and unusual historic material. Also called Capitol Marble, this Triassic conglomerate is featured as the columns in the US Capitol National Statuary Hall rotunda. They hold up the main Capitol Dome. Interestingly, the location of the quarry where this material was mined was lost for 200 years. But the old quarry site was finally found a few years ago. We visited the site which is along the C & O canal (near milepost 38) in 2024. It hosts the exact same rock we collect for carving at Point of Rocks, some 12 miles upstream where this piece is from. This freeform was sculpted by Jon in 2022 and has a flat bottom for easy display. It features a highly polished partial helix on the front and a contrasting natural back, showing how the rock is found in its rough state.
HOW IT FORMED
Paleozoic mountains that were being uplifted during the Triassic Period as North America and Africa were colliding. About 205 million years ago these rivers carried broken pieces of dolomite into a basin where they were buried. As the layers accumulated in depth, heat and pressure built up and eventually cemented everything together. Later the layers were pushed up and erosion removed the sediments above, exposing this unique rock in certain locations along the Potomac River.
SIZE: 6″ x 4″ x 6″
AGE: Triassic Period, 205 million years
UNIT: Newark Supergroup
SITE: Point of Rocks, Maryland
DATE: 2021Documentation: This authentic fossil specimen comes with a Certificate of Authenticity and Origin.
$525.00Potomac Marble Sculpture
$525.00 -
Rainbow Stromatolite (RS1)
Notes specific to this specimen: This is one of the original discovery pieces, collected by us in August 2025. It is characteristic of all the variety of colors found in this site. We’ve never seen such a variety of colors of stromatolite from a single site. It reminded us of all the colors of Arizona petrified wood – known as “Rainbow Wood” – and this became the source for our naming this new discovery “Rainbow Stromatolite”.
SIZE: 2″x 4″x 1.5″
Name Collenia sp. (possible new species)
Age Anamikean / Paleoproterozoic – 1.88 billion years
Unit Gunflint Iron Formation
Site Ontario, Canada
Date 2025Documentation: This authentic fossil specimen comes with a Certificate of Authenticity and Origin. In addition, an attractive and informative display card accompanies the specimen.
$285.00Rainbow Stromatolite (RS1)
$285.00 -
Rainbow Stromatolite (RS2)
Notes specific to this specimen: Another one of the original discovery pieces, collected by us in August 2025. Unusual wine coloring with distinct colonies.
SIZE: 1.5″x 4″x .5″
Name Collenia sp. (possible new species)
Age Anamikean / Paleoproterozoic – 1.88 billion years
Unit Gunflint Iron Formation
Site Ontario, Canada
Date 2025Documentation: This authentic fossil specimen comes with a Certificate of Authenticity and Origin. In addition, an attractive and informative display card accompanies the specimen.
$110.00Rainbow Stromatolite (RS2)
$110.00 -
Rainbow Stromatolite (RS3)
Notes specific to this specimen: Another one of the original discovery pieces, collected by us in August 2025. Deep red colonies surrounded by high iron hematite matrix.
SIZE: 2″x 2.58″x .75″
Name Collenia sp. (possible new species)
Age Anamikean / Paleoproterozoic – 1.88 billion years
Unit Gunflint Iron Formation
Site Ontario, Canada
Date 2025Documentation: This authentic fossil specimen comes with a Certificate of Authenticity and Origin. In addition, an attractive and informative display card accompanies the specimen.
$120.00Rainbow Stromatolite (RS3)
$120.00 -
Rainbow Stromatolite (RS4)
Notes specific to this specimen: Another one of the original discovery pieces, collected by us in August 2025. Unique honey-color colonies with unusual dark laminae. Never seen anything like this!
SIZE: 2″x 2″x .75″
Name Collenia sp. (possible new species)
Age Anamikean / Paleoproterozoic – 1.88 billion years
Unit Gunflint Iron Formation
Site Ontario, Canada
Date 2025Documentation: This authentic fossil specimen comes with a Certificate of Authenticity and Origin. In addition, an attractive and informative display card accompanies the specimen.
$165.00Rainbow Stromatolite (RS4)
$165.00 -
Rainbow Stromatolite (RS5)
Notes specific to this specimen:Â Another one of the original discovery pieces, collected by us in August 2025. Wild contrasts in the colors of these colonies.
SIZE: 2″x 4″x .5″
Name Collenia sp. (possible new species)
Age Anamikean / Paleoproterozoic – 1.88 billion years
Unit Gunflint Iron Formation
Site Ontario, Canada
Date 2025Documentation: This authentic fossil specimen comes with a Certificate of Authenticity and Origin. In addition, an attractive and informative display card accompanies the specimen.
$150.00Rainbow Stromatolite (RS5)
$150.00
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