Parking Block White
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 (27 POIs)
Grover High (tier 5), Navezgane County Jail (tier 5), Two Bit Tower (tier 5), U.S. Army Post #7 (tier 5), Aranea Caverns (tier 4), Favales Academy (tier 4), Granddaddy's Cable Regional Service Center (tier 4), Hotel Zombona (tier 4), Ironwood Paper Mill (tier 4), Water Works (tier 4), Working Stiff Superstore (tier 3), Crypts (tier 2), Electric Company (tier 2), Historic Office Suites (tier 2), Palo Verde Brickworks (tier 2), Treats Terrace (tier 2), Echo Commons (tier 1), KZZ Radio Station (tier 1), Pass-N-Gas Store #09 (tier 1), Buffalo Blues Building, Hobo Camp, Marlon's Kart Track, Natas Parking, Quiet Corner, Route 66 Restaurant Row, Willtronics Corner, ZBrews Row.
Points of interest built with this block (any of its variants), the highest tiers first, from the game's prefab files.