Nubatama Ume #25 (XXXC Black Aratae)
Complete
$60.21
Skip to product information
Nubatama Ume #25 (XXXC Black Aratae)
$60.21
11 in stock
The coarsest stone in the Nubatama lineup. Ken Schwartz used it for two things: heavy grinding on badly damaged edges, and dressing coarse stones back to an aggressive cut.
| Feature | Specification |
|---|---|
| Brand | Nubatama |
| Type | Synthetic |
| Grit | #25 (XXXC — Extra-Extra-Extra Coarse) |
| Series | Ume (Black Aratae) |
| Binder Hardness | Standard |
| Profile | 205 × 75 × 50mm Brick |
Buy This Stone If You're
- Resetting a primary bevel or grinding out severe damage.
- Restoring cutting aggression to coarse stones that diamond plates have burnished.
- Flattening coarse stones and want to skip loose silicon carbide powder.
Water
Nubatama range stones should not be permasoaked. Let dry fully before storage; coarse stones hold water a long time.
Progression Ideas
- Preceding Step (Lower Grit): None — this is the entry point.
- Following Step (Higher Grit): Nubatama Bamboo #150, or the Ume #60 for a shorter jump.
Ken Schwartz Video
Notes
- Often referred to as the 24-grit. Same stone.
- Boxes are marked with Japanese characters rather than a grit number.
- Two of these dress each other flat. A diamond plate leaves the surface too fine.
- Too rough for re-establishing bevels on ordinary kitchen knives — this is a repair and stone-dressing tool.
Read More
- Stone Flattening — Shapton Glass – Why a diamond plate cuts through the abrasive grains and leaves a coarse stone flat but far less aggressive.
- Flattening Stone – Owning one or two of these, and cutting a small piece down as a dedicated dressing block.
- Universal Stone Holder Question – Why the Aratae itself needs a second Aratae rather than a diamond plate to stay aggressive.
- Nubatama Ume XXC Aratae 24 Grit And 60 Grit Stones – An owner reprofiling two axes and repairing a D2 tip, with notes on dishing.
- Stone For Major Reprofiling And Thinning Projects – Owners weighing the 24 against the 60 for heavy reprofiling, and how each glazes.
- Learn From My Mistakes… Stones Cracking – Permasoaking and drying guidance for the full Nubatama range, and why it matters.
Condition
- Stone: New and unused.
- Packaging: While our inventory is new, the original packaging may show minor shelf wear, scuffing, or external softening due to warehouse storage and handling over the last five years. Internal protective wrapping (plastic or paper) may show signs of handling, minor tears, or may occasionally be absent—this never affects the condition of the stone itself.
Shipping
Orders are typically processed and shipped same day from Santa Maria, CA.
Every stone ships in a new, high-quality box, individually wrapped in bubble wrap and packing paper for maximum protection in transit.
Please reach out with any questions before or after purchase — happy to help.
Return policy
At Pacific Waterstone, we stand behind the authenticity and quality of every stone we sell.
Incorrect or Mislabeled Items
If you receive an item that is mislabeled, damaged, or significantly mischaracterized in its listing, we will make it right. You may return the item for a full refund or exchange with no restocking fees, and we will cover all return shipping costs.
Standard Returns
If you change your mind or wish to return an item for any other reason:
- Returns are accepted within 14 days of delivery.
- Items must be returned in their original, unused condition with all original packaging.
- A 10% restocking fee applies to cover processing costs.
- Return shipping costs are the responsibility of the customer.
To initiate a return, please contact us with your order number and the reason for your request.
Provenance
Everything we carry comes from the personal collection of Ken Schwartz — the sharpener behind Precise Sharpening, who built the Nubatama line and gathered the naturals that sat beside it on his bench. The synthetics are new and unused. The naturals were his.