The 1x6" Naniwa Chosera 5K Grit stone is the first real polishing stone of the Chosera series. This stone is best used after a medium grit (1K-4K) stone to really start bringing out hair shaving sharpness and shine, and to prepare the edge for higher polishing grits, but it can still be used for light touching up and routine maintenance on dull, but otherwise intact, edges. It leaves a mirror polished work sharp edge that is more than acceptable for almost any knife or tool.
1" x 6" x 5mm in size and mounted to a steel blank, the 1K Chosera is used with water only and works best when soaked in water for a minute or two before use. Store in a dry place in between use.
Abrasive: Aluminum Oxide
Ideal place in a sharpening progression:
The 5K Grit Naniwa Chosera sharpening stone is a premium sharpening stone that works on almost all types of knives, scissors, tools and chisels, including those made with abrasion resistant steels. Even though the 1x6 size is meant for use with the Edge Pro, Hapstone and TSProf sharpeners, it is also a great size for a slip stone, field stone or a pocket stone for knife sharpening on the go, or to remove unwanted burrs.
On More Traditional Carbon Steel and Stainless Steel Edges, the 5K Chosera stone works on steels between RC 52 and RC 65 on the Rockwell C Hardness scale. On softer end stainless steels used by many kitchen knife makers like Henckels, Wüsthof, Gunter Wilhelm, F Dick, Victorinox, etc. such as X50CrMoV15, AUS6, 440B, this 5K stone leaves a highly polished edge that is more suited to slicing. On these steel types, stone can maintain a serviceable edge, but does require a lower grit stone for any real damage or change in profile. Also, the structural characteristics of the steel may get close to reaching its upper limits at this grit.
On the higher end of the hardness spectrum of traditional steel edges made with steels like 1095, 52100, 440C, Aogami White, Shirogami Blue, O1, W1, etc. The Chosera 5K establishes a full on mirror finish with a slicing edge. It can be used to maintain the sharpness, but will require a coarser grit stone to do more serious repairs or profiling. These harder steel types thrive in this higher grit atmosphere, and 5K can be a versatile final grit, or just the beginning of the journey to finer stones and stropping.
On Carbide Forming Steel and More Abrasion Resistant Steel Edges such as VG-10, D2, M2, S35V, S90V, etc., The 5K Chosera stone is a pure polishing stone and requires a properly prepped edge from lower grits in order to bring out the maximum potential of the shine. The cutting edge off the 5K is more slicing, but the carbides still give the edge some stiffness and bite. The edge off this stone can be used as is, or to be further refined with stropping or finer grits stones.
Hacks and Tips:
Choseras are waterstones, and are not to be used with oil, but can be used in conjunction with oil stones (such as Norton India and other carborundum and Arkansas stones) if the blade is wiped clean before and after switching stone types. They can also be used in a mix and match progression with other synthetic and natural sharpening stones, as well with other brands such as Shapton, Sigma, Suehiro, Imanishi, Spyderco, King, etc. Naniwa Chosera is the original name of this stone line, and is now rebranded as Naniwa Professional Stones.
Comparable Stones: Shapton 5K, Jende 6K SPK, Suehiro Cerax 5K, Sigma Select II 6K
Alternative Mid Range Stones: Jende 4K Frenchs, Naniwa 4K Finisher