Shobudani Awasedo #057

Description & Classification
Mine & Strata: Shoubudani Eastern mine, Awasedo finishing strata, confirmed by the boxed kanji stamp. 
Color & Purity: A pale, mustard-buff Kiita . The face shows exceptional visual purity and even grain structure without inclusions or intrusive inclusions across the primary sharpening track.  
Mass & Dimensions: Measured weight of 1,265 g (approx. 2.79 lbs), placing it in the substantial full-sized Standard 30 / 24-size bench stone class rather than a small nagura or palm piece.  
Profile & Cut: Semi-rectangular Koppa / bench format featuring a straight, sawn long edge, a square base end, a cleaved taper on the left flank, and an angled natural cleavage facet at the top-right corner.  
Base (Skin): Raw natural bedding skin (kawa) displaying a waffle/grid iron oxide mottled pattern from quarry separation, typical of dense Eastern mine Awasedo layers.  
Hardness & Grit Rating: Estimated Lv 4.0 – 4.5 hardness, delivering an equivalent refinement range of 8,000 to 12,000+ grit with consistent feedback and speed.
Flaw & Condition Documentation
Cleaved Left Flank (Corner Inclusion): The lower-left corner shows a diagonal shelf fracture where the natural bedding broke away, reducing usable width at that corner but leaving the main rectangular surface intact.  
Angled Top Corner: The upper right perimeter is chamfered along cleavage planes, requiring angled stroke adjustments when working wider blades over the area.  
Underside Irregularity: The waffle-patterned reverse face is raw even and stable.
Sealed Perimeters: The sides and back are completely sealed.
Micro-lines: A faint, tight natural grain seam is visible under close inspection across the mid-face; it is flush, non-toxic, and does not catch a fingernail or blade bevel.  
Performance & Steel Compatibility
Sharpening Feedback: Hard, smooth, and fast-cutting once surfaced. It responds best when primed with an Atoma 1200 or fine Tomo Nagura to build a creamy, yellow-tinted slurry before transitioning to pure water for the final edge alignment.
Kasumi & Edge Contrast: Yields a semi-mirror core steel polish accompanied by a creamy, cloud-like kasumi mist on softer cladding (iron, nickel, or damascus), making it well-suited for fine Japanese kitchen blades, kanna irons, and straight razors.