Parking Block Grey
A composite material composed of sand, stone, and cement. This block can not be upgraded and is likely only found in the creative menu.
Harvest drops
Small Stone× 25
Taken apart with a harvesting tool (axe, pickaxe, shovel), before perks and tool bonuses.
When it collapses
Falling, it leaves 
Destroyed Stone (75% of the time) where it lands.
Where to find (34 POIs)
7 Days Suites (tier 5), Area 7 (tier 5), Navezgane Corrections (tier 5), Ostrich Hotel (tier 5), Pop-N-Pills Factory (tier 5), Don Vittorio Spagetto Residence (tier 4), Good Life Apartments (tier 4), Pineballs Bowling (tier 4), Shotgun Messiah Range (tier 4), Town Hall (tier 4), 4 Ever Video (tier 3), Elzner's Emporium (tier 3), Happy Sleep Motel (tier 3), Jim & Tim's Bullets and Booze (tier 3), Wildfire Camping (tier 3), Federal Appliance (tier 2), Grumpy's Pub (tier 2), Maggie's Corner Cafe (tier 2), McPherson UFO Museum (tier 2), Nick's Motel (tier 2), The Budget Burrows (tier 2), Buzz's Bar (tier 1), Joe's USA (tier 1), MoPo-Shack (tier 1), Motel Eight (tier 1), Pass-N-Gas Store #02 (tier 1), The Greasy Spoon (tier 1), Bloomington Square, Derelict Warehouse, Fallen Rock Apartments, Perishton, Shamway Processing, Trader Hugh, Trader Jen.
Points of interest built with this block (any of its variants), the highest tiers first, from the game's prefab files.