Felbrigg War Memorial is a sandstone memorial, the material being chosen to match the sandstone of nearby Felbrigg Hall. It comprises a Latin Cross on a square plinth, and contains the names of the twelve men of the village that fell in World War One. It also contains the following inscription;
To keep in memory the men of Felbrigg who fell in the Great War
Their name liveth for evermore
1914 - 1918
Sandstone is a sedimentary rock made mainly of sand-sized mineral grains—most often quartz and sometimes feldspar—cemented together by natural mineral “glue” such as silica, calcite, or iron oxides.
Sandstone formation
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Weathering & erosion – Rocks (especially granite or other quartz-rich rocks) are broken down by wind, water, and temperature changes, producing loose sand grains.
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Transportation – These sand particles are carried by rivers, wind, glaciers, or waves to new locations, often ending up in riverbeds, beaches, or deserts.
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Deposition – Over time, layers of sand settle in basins, deltas, or shallow seas.
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Burial & compaction – More layers build up above, pressing down on the sand below and squeezing out water and air.
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Cementation – Minerals dissolved in groundwater precipitate between the grains, cementing them together into solid rock.
In short, sandstone is loose sand turned to stone by compaction and cementation—a process called lithification.
Shell Fragments
sandstone can contain shell fragments, but it depends on how and where it formed.
If the sand was deposited in a marine or coastal environment, it might also trap bioclastic material such as broken shells, coral pieces, or other skeletal debris.
When sandstone contains a lot of shell material, geologists often call it a calcarenite (if it’s mostly calcium carbonate shells) or bioclastic sandstone.
Other sandstones without shell fragments include:
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Arkose or feldspathic sandstones (if deposited in non-marine environments like rivers or alluvial fans).
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Lithic sandstones from continental or volcanic sources that never interacted with abundant marine life.
Here’s a simple but accurate chart for common sandstone types and their tendency to contain shell fragments.
| Sandstone Type |
Contains Shell Fragments? |
Notes |
| Quartz arenite |
Rare |
Mostly pure quartz grains, well-sorted, little to no fossils. |
| Arkose |
Rare |
Rich in feldspar; shell material uncommon. |
| Lithic sandstone |
Occasional |
Rock fragments dominate; fossil content varies with source. |
| Feldspathic wacke |
Occasional |
Poorly sorted; fossils possible but not common. |
| Calcarenite |
Common |
Made largely of shell fragments and carbonate grains. |
| Bioclastic sandstone |
Very common |
Specifically made from broken shells, corals, and other skeletal debris. |
Sandstone weathering
Sandstone weathers in different ways depending on its mineral composition, cement type, climate, and exposure conditions, but the main weathering processes can be grouped into Mechanical (physical), chemical, and Biological weathering.
1. Physical (Mechanical) Weathering
This breaks sandstone apart without altering its mineral composition.
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Freeze–thaw action: Water enters tiny cracks and pores, freezes, and expands, causing the rock to fracture.
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Thermal expansion: In hot, dry climates, daytime heating and nighttime cooling make the minerals expand and contract at different rates, leading to flaking or splitting.
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Salt crystallization: In coastal or arid regions, salty water evaporates in the rock’s pores, and growing salt crystals exert pressure that dislodges grains.
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Abrasion: Wind-blown sand or flowing water grinds away the surface.
2. Chemical Weathering
This changes the minerals in the sandstone, weakening the rock.
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Hydrolysis: Common in feldspar-rich sandstones; water reacts with feldspar to form clay minerals, loosening the rock structure.
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Oxidation: Iron-bearing minerals (like magnetite or biotite) oxidize, producing rust-colored stains and weakening cement.
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Dissolution: If the cement is calcite (CaCO₃), acidic rainwater can dissolve it, making the sandstone crumbly.
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Silica dissolution: Very slow, but in humid conditions, even quartz cement can gradually dissolve.
3. Biological Weathering
Living organisms contribute to breakdown:
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Root growth: Plant roots force their way into cracks, prying the rock apart.
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Lichen and moss: These secrete weak acids that chemically attack minerals while also trapping moisture for physical weathering.
Study this War Memorial and answer these four simple questions;
1. Of the five different types of sandstone that are listed above, what type of sandstone do you think the War Memorial is made of, and what makes you think so?
2. After studying the War Memorial, what type of environment do you think the Stone was formed in, and please explain why you think so?
3. Please comment on the weathering that the War Memorial has suffered. What types of weathering are visible would you say?
4. COMPULSORY. Please take a picture of yourself, your GPS device or a personal item or a photo at GZ with your name visible, preferably with the War Memorial or the Village Sign in the background and please be careful that your picture does not give away any answers.
Please feel free to log a find straight after you have sent me your answers. All answers will be looked at and if there are any issues I will contact you. ANY found logs without a photo and any found logs without answers submitted within a reasonable period will be deleted. This is to ensure fairness to those cachers who do complete the tasks required.
***** PLEASE NOTE IMPORTANT *****
CACHES ARE NOT ALLOWED TO BE PLACED ON ACTUAL MEMORIALS OR WITHIN THE BOUNDARY OF SUCH
AT ALL TIMES PLEASE TREAT LOCATIONS OF MEMORIALS WITH RESPECT