King water stones

Step into the world of a legend that forever changed the face of sharpening – meet King stones, the creation of Matsunaga Stone Co., Ltd. from Osaka, where the history of synthetic water stones has been written since 1948. This isn’t just a brand—it’s a pioneer of the revolution that brought the ancient Japanese craft of sharpening into the modern era, all while preserving the spirit of traditional mastery passed down through generations.

The Genesis of the Osaka Revolution

The King story begins with the visionary idea of the Matsunaga founders, who, in post-war Japan, recognized the need to democratize access to high-quality sharpening tools. Traditional natural stones from the Yamashiro and Yamato regions were expensive, hard to obtain, and characterized by inconsistent quality. Matsunaga set an ambitious goal—to create a synthetic water stone that would combine the predictability and consistency of modern manufacturing with the unparalleled sharpening properties of natural Japanese stones.

The groundbreaking discovery occurred in the Matsunaga laboratories in the late 1940s, where engineers developed a unique formula based on specially prepared grains of aluminum oxide (corundum) combined with an advanced ceramic binder system. This composition, refined over decades, became the foundation of all King stones and remains a closely guarded company secret to this day. The key to success was achieving the perfect balance between hardness and wear—the stone had to be hard enough to effectively sharpen steel, yet soft enough to continually expose fresh layers of abrasive material during use.

The first series of King stones hit the market in 1950 and immediately revolutionized the way Japanese craftsmen approached sharpening their tools. The accessibility, consistency, and reliability of these stones quickly gained popularity not only among professionals but also among everyday users who, for the first time, could afford master-level sharpening tools. The word “King” in the name was no accident—it was meant to symbolize the brand’s royal aspiration to be the best in its class.

The Alchemy of Corundum – Secrets of King Production

The base material of King stones is corundum (Al₂O₃)—one of the hardest naturally occurring minerals, with a Mohs hardness of 9 (only diamond is 10). However, not all corundum is suitable for manufacturing sharpening stones. Matsunaga exclusively uses electro-fused corundum, produced under controlled industrial conditions, which guarantees ideal chemical purity and crystalline structure uniformity. The grain preparation process includes multi-stage sorting according to size, shape, and mechanical properties—each batch undergoes rigorous quality testing before entering production.

The secret to the soft structure of King stones lies in the special ceramic binder technology, which binds the corundum grains in a way that allows for controlled release of the abrasive material during sharpening. This binder, developed exclusively for Matsunaga, is characterized by unique porosity, enabling rapid water absorption and the creation of abundant slurry during use. The firing process of the stones takes place under precisely controlled temperature-time conditions, where each phase is crucial to the final properties of the product.

The characteristic slurry produced during sharpening on King stones is not a side effect but an integral element of the sharpening process. This creamy mixture of water, fine corundum particles, and metal filings acts as an additional abrasive medium that “refines” the blade’s surface on a microscopic level. The abundance of slurry means the stone is constantly exposing fresh layers of abrasive material, which translates to consistent sharpening effectiveness regardless of the working time. This is a property that most competing stones don’t offer, making King unique in the market.

The Full Spectrum of Grits – From Restoration to Perfection

King Home #220 – The Power of Restoration

The most aggressive in the King lineup, the #220 stone is the tool for salvaging completely dull or damaged blades. Its coarse-grained structure allows for the rapid removal of deep chips, corrosion, or deformation, restoring the knife’s basic geometry. Despite its power, it maintains the characteristic gentleness of the entire King line, without introducing excessive stress into the steel structure. This is the stone for those who need to bring life back to knives others have deemed hopeless.

King Deluxe #400 – The Foundation of Sharpness

The #400 grit is a universal soldier in every sharpener’s arsenal. Aggressive enough to remove more significant damage, yet precise enough not to leave deep scratches on the blade surface. This is the stone chosen by professionals as the starting point for most sharpening procedures, and its versatility makes it potentially the only stone needed in a hobbyist’s kitchen.

King Deluxe #1000 – The Heart of Japanese Sharpening

The most recognizable stone in the history of Japanese sharpening, #1000 is the grit where most enthusiasts begin their journey. This is the stone that taught the world what true Japanese sharpening is—combining effectiveness with pleasure of use. Its ideal balance between aggressiveness and delicacy makes it equally effective for regular maintenance and for more serious repairs.

King Deluxe #1000/6000 – The Icon of Double-Sidedness

The legendary double-sided stone KW-65 is probably the most famous sharpening stone in the world. The #1000 side provides effective sharpening, while the #6000 side gives blades a mirror polish and razor sharpness. This is the stone that changed the way people think about home sharpening, proving that professional results are accessible to everyone.

King Deluxe #6000 – The Mastery of Finishing

The #6000 stone is an artistic instrument that transforms a functional edge into a work of art. This grit allows for achieving a mirror-smooth surface that not only looks beautiful but also provides unparalleled sharpness and cutting edge durability. This is the stone for perfectionists who understand that sharpening is not just a necessity but a form of artistic expression.

King Deluxe #8000 – The Peak of Evolution

The newest addition to the King family, the #8000 stone represents the peak of Matsunaga’s technological capabilities. This ultra-fine grit allows for polishing the blade to a level previously only available using natural stones costing thousands of dollars. This is a tool for masters who accept no compromises in the pursuit of absolute perfection.

The Soaking Ritual – Meditation Before Sharpening

Every King stone requires a soaking ritual—a process that is more than just technical preparation. It is a time for focus and mental preparation for work that demands precision and patience. 10-15 minutes of soaking in cold water is the moment to prepare the knife, clear the mind, and get ready for the meditative process of sharpening.

The characteristic bubbles rising from the stone during soaking are visual confirmation that the porous structure is saturating. When the flow of bubbles stops, the stone is ready to work. This simple indicator allows even beginners to precisely determine the moment of optimal preparation, eliminating guesswork and uncertainty.

During sharpening, the stone must be regularly moistened with water—not only to maintain slurry formation but also to prevent the steel from overheating. This element of the sharpening rhythm eventually becomes a natural, automatic gesture that further calms and organizes the thought process.

The Dedicated Base – Stability in Every Detail

Every King Deluxe stone comes with a dedicated plastic base, equipped with non-slip rubber inserts. This solution, which might seem like a simple accessory, is actually crucial for the safety and effectiveness of sharpening. The stable base eliminates stone movement during work, allowing for full concentration on angle control and pressure.

The ergonomic properties of the base also account for hygiene—the possibility of easy washing and quick drying prevents the growth of bacteria and mold. Drainage holes in the base allow for quick removal of excess water, shortening the drying time of the stone after use.

Versatility of Application – More Than Just Knives

King stones are universal tools that find use far beyond the kitchen. Woodworkers and sculptors appreciate their effectiveness in sharpening chisels, gouges, and planes. Gardeners use them to maintain the sharpness of pruners, shears, and sickles. Artists and craftsmen use the delicate grits for precise sharpening of engraving and carving tools.

Compatibility with various types of steel means King performs equally well with the carbon steel of Japanese knives as it does with modern stainless steels or composites. This versatility makes King the first choice for workshops, schools, and studios where tools made of different materials are used.

The Philosophy of Accessibility – Quality for Everyone

King’s mission from the very beginning has been the democratization of high-quality sharpening. Unlike exclusive natural stones, available only to a select few, King offers the highest quality at an affordable price. This approach has allowed millions of people around the world to discover the joy and satisfaction that comes from properly sharpening their tools.

The ease of use of King stones means that even inexperienced people can quickly achieve satisfactory results. The soft, forgiving structure tolerates technical mistakes, not punishing them with deep scratches or blade damage. These are stones that teach, allowing for learning through practice without fear of irreversible harm.

Heritage and Future

For over 75 years, King stones have served successive generations of sharpening enthusiasts, passing on not only technical skills but also a philosophy of respect for tools and the pride of a job well done. This is a brand that has trained masters—many of today’s best chefs and craftsmen began their sharpening journey with King stones.

Today, in the era of digitization and automation, King stones remain an oasis of authenticity and manual craftsmanship. In a world where everything must be fast and easy, King reminds us of the value of patience, precision, and the satisfaction that comes from the masterful command of traditional skills.

King water stones are more than tools—they are bridges connecting the modern world with the Japanese tradition of perfection in every detail. By choosing King, you choose a heritage that has inspired people worldwide for over seven decades to discover the joy and satisfaction of true craftsmanship.