Basalt contains iron. Iron is very heavy. Sand bags are too thin and too large. The weight of a sand bag containing basalt would be too heavy to place on your body and to lift.
Sand bags are porous. Sand comes out of them. Makes a mess. Harmful to inhale. I had to double sand bags to keep sand in them.
Super crates construct the head crate.
Crates have holes. 3/8 to 5/8 inch basalt buttons go through these holes. I pack approximately 5 pounds of basalt buttons into a Mainstays lingerie mesh bag. These bags are not heavy duty. The weight they can hold is limited. They were the lowest priced mesh bags I could find.
Possibly larger gravel could be mixed in with smaller gravel
What do you mean by "larger gravel?" Gravel is made of granite, shale or some other rock. Gravel is not made of basalt.
By "larger gravel", if you mean basalt, don't use the term gravel. If you type gravel in a search engine, basalt will not come up. Sellers of basalt do not use the term gravel. If you mean larger gravel such as 3/8 to 5/8 inches that are long shape, use the term pebbles. If you mean round 3/8 to 5/8 inches, use the term buttons. These are the terms sellers of basalt use. If you had looked at online advertisements for basalt, you would have know this.
There are two types of Mexican Black Beach Pebbles, La Paz and San Quintin. While both stone types are smooth the San Quintin stones are more flat and oblong. La Paz material is more fat and round, thus cobble like. San Quintin stones are hand harvested from the beaches of the Pacific Coast of Baja California couple of hours south of Ensenada, Mexico.
https://www.earthstonerock.com/Mexican-Beach-Pebble-Buttons-1-2-For-Sale-p/dg203x50.htm
Use the term criva if you mean very small basalt. Criva is sold in two sizes: 1/8 to 1/4 inches long and 1/4 to 1/2 inch long.
https://www.coverallstone.com/decorative-pebbles/mexican-beach-pebble/black-criva
Mixed colors criva basalt 1//8 to 1/4 inch long.
https://sepulveda.com/product/mexican-beach-pebble-mixed-18-14
Mixed colors criva 1/4 to 1/2 inch.
https://sepulveda.com/product/mexican-beach-pebble-mixed-14-12
Never dilute or mix materials that shield with materials that do not shield. Shielding requires 100% materials that shield. Gravel does not shield.
Never use a material that does not shield unless you intentionally want to use a spacer to take up space in a head crate. For example, in the radio quiet zone, I used a six inch spacer in the side super crates. The interior of the super crates is 12 3/4 inches thick. Having turned off all the circuit breakers in my summer home and disconnecting my car battery, 12 3/4 inch thick basalt 3/8 buttons in the side super crates were not required. I tested and discovered 6 3/4 inch sides were adequate. So I removed some basalt and added a spacer.
In California in 2022, I had to decreased the spacer from 6 inches to 3 inches. In the Space Coast, Florida, I removed the spacer. The thickness depends on whether all the circuit breakers are off in the home, the car battery is disconnected, whether one resides in a radio free zone and whether the local military base is high tech.
then you could mix in the more expensive basalt dust to help fill in the gaps between stones
Dust would not shield. Minimum depth of basalt to shield laser is 2 1/2 inches.
Basalt is not sold as a dust. The smallest basalt is criva.
https://www.coverallstone.com/decorative-pebbles/mexican-beach-pebble/black-criva/
1/8 inch criva would fall through the 3/16 inch holes of the Mainstay lingerie mesh bags.
Of course, criva would fall through the holes of the super crate.
Criva would create a better bed pillow. Criva inside of a 18" x 18" bed pillow would be more comfortable than 3/8 to 5/8 inch buttons inside of a bed pillow.
Criva inside of a plastic slider bag inside of a large cosmetic bag inside of a wrap. Wrap the wrap around one's stomach or back.
https://www.reddit.com/r/TargetedEnergyWeapons/comments/ctkwlp/shielding_rocks_wet_rock_belly_wrap/
Very few retailers sell criva. Criva is more expensive than small pebbles. The military repeatedly steals shielding. Replacing criva numerous times will be costly unless you reside near Baja California or the states bordering Mexico.
https://www.reddit.com/r/TargetedEnergyWeapons/comments/10nlsut/wiki_shielding_thefts_and_vandalism/
I have not tested criva. Since 3/8 to 5/8 inch buttons shield very well and are cheaper than criva, they are fine.
There are no visible gaps between 3/8 inch basalt rocks. There will be gaps between larger rocks. Don't use larger rocks.
Could put them in cheap 50 cal ammo cans for $10 that are 11x 5.5 by 7 inches.
There would be gaps between ammo cans. All weapons can penetrate gaps. There are barely any gaps between mesh bags.
These will be easy to position to create a uniform wall around your head and provide their own structure.
A wall of ammo cans? That is ridiculous. Read the head crate wikis in the shielding: rocks: basalt wiki. Super crates provide the structure.
These are far too expensive to use to construct an actual wall for larger enclosure though.
Shipping is expensive. Price of gasoline increased.
Numerous repeated thefts of shielding materials. Especially basalt. Multiple replacements.
If you relocate to a town that has native basalt in parks or beaches or if you relocate to a town that imports mexican beach pebbles from Baja, California, criva may be affordable. Criva is human made. Criva is not natural formed. Criva is not found where native basalt rocks are. My kidneys were lasered while I was collecting basalt from dry rivers in Arizona. There was no criva. Please do volunteer to research where to buy basalt and comment in this wiki:
I edited this post to make it clearer.