Mirror stainless steel sheets have become a popular choice in architectural design, decoration, elevators, and industrial applications due to their elegant appearance and excellent durability. Their highly reflective surface adds luxury, depth, and brightness to any environment. However, not all mirror finishes are the same — there are different surface grades that define the level of reflectivity, smoothness, and polish.
In this article, SAKYSTEEL explains the various surface grades of mirror stainless steel sheets, how they are produced, their unique characteristics, and how to choose the right grade for your application. Understanding these grades helps designers, fabricators, and end-users make informed decisions to achieve the perfect balance between performance and aesthetics.
What Is a Mirror Stainless Steel Sheet?
A mirror stainless steel sheet is a flat piece of stainless steel that has been polished to a highly reflective, glossy finish. It reflects light and surrounding objects almost like a glass mirror. The process of achieving this finish involves multiple polishing and buffing stages using abrasive compounds and soft wheels to eliminate scratches and surface irregularities.
Mirror finishes not only improve visual appeal but also enhance the steel’s resistance to corrosion by sealing microscopic surface pores. The smoother the finish, the better it performs in terms of hygiene, cleanliness, and oxidation resistance.
At SAKYSTEEL, each mirror stainless steel sheet undergoes rigorous polishing and inspection to ensure a distortion-free, high-gloss surface suitable for both decorative and functional uses.
The Importance of Surface Grades
The surface grade of a mirror stainless steel sheet refers to the level of polish and reflectivity achieved during the finishing process. Each grade corresponds to a specific step of polishing and determines the final appearance, texture, and clarity.
These grades are often standardized using the AISI/ASTM surface finish classifications, which range from mill finishes like No.1 and 2B to high-polish grades like No.7 and No.8.
Common Surface Grades for Mirror Stainless Steel Sheets
Let’s explore the main surface grades and what they represent in terms of production method, appearance, and application.
No. 2B Finish – The Base for Polishing
No. 2B finish is not yet a mirror surface, but it’s the most common base material used for producing mirror sheets. It’s obtained through cold rolling, annealing, and pickling, followed by a light skin pass with polished rolls.
Features:
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Smooth but dull, gray surface
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Serves as an excellent starting point for mirror polishing
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Economical and widely available
Applications:
Used as base material before further polishing to higher grades like No.7 or No.8.
No. 4 Finish – Brushed or Satin Surface
The No.4 finish is produced by grinding the surface with abrasive belts (typically 150–240 grit). It has a matte appearance with fine parallel lines and is not reflective. However, it’s often used as an intermediate step before higher polish grades.
Features:
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Brushed texture with directional grain lines
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Easy to clean, hides fingerprints
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Not a mirror finish but provides good groundwork
Applications:
Kitchen appliances, elevators, decorative panels, and control cabinets.
No. 6 Finish – Semi-Mirror Polish
The No.6 finish offers a semi-reflective surface, smoother than No.4 but not fully mirror-like. It’s achieved through additional fine polishing using soft abrasive materials or non-woven brushes.
Features:
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Soft gloss, low reflectivity
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Slightly hazy reflection
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Good combination of appearance and durability
Applications:
Used where moderate reflection is acceptable, such as interior panels and equipment covers.
No. 7 Finish – Bright Mirror with Minor Haze
The No.7 finish is the first true mirror-grade surface, created by further polishing the No.6 finish with finer abrasives and buffing compounds. It provides a bright, reflective surface but may still show slight polishing lines or haze under strong light.
Features:
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High reflectivity with slight distortion
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Fine, clear reflection with minimal grain visibility
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Smooth touch and improved corrosion resistance
Applications:
Elevator interiors, architectural claddings, signage, and high-end decorative elements.
Production Notes:
Polishing sequence typically involves abrasive belts from 400 to 1200 grit, followed by soft cloth buffing with alumina-based compounds.
No. 8 Finish – True Mirror Finish
The No.8 finish, often referred to as super mirror or mirror #8, represents the highest grade of mirror polish available for stainless steel sheets. This finish is completely smooth, reflective, and free of visible lines or distortions.
Features:
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True mirror-like reflectivity
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Distortion-free surface with exceptional brightness
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Extremely low surface roughness (Ra < 0.05 μm)
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Excellent corrosion resistance due to smooth surface
Applications:
Luxury architecture, decorative interiors, hotel lobbies, art installations, and clean environments such as medical or food-processing facilities.
Production Process:
Multiple polishing stages using progressively finer abrasives (up to 3000 grit) followed by buffing with soft cotton wheels and polishing waxes.
At SAKYSTEEL, our #8 Mirror Finish Stainless Steel Sheets are polished with advanced automatic mirror lines, ensuring uniform gloss, reflection consistency, and superior surface clarity across large sheet sizes.
Comparison of Mirror Surface Grades
| Grade | Appearance | Reflectivity | Surface Roughness (Ra) | Application Examples |
|---|---|---|---|---|
| No. 2B | Dull, smooth gray | Low | 0.15–0.2 μm | Base material for polishing |
| No. 4 | Brushed matte | Moderate | 0.1–0.2 μm | Kitchen equipment, panels |
| No. 6 | Semi-gloss | Medium | 0.08–0.1 μm | Interior fittings |
| No. 7 | Bright mirror with light haze | High | 0.05–0.07 μm | Elevators, decorations |
| No. 8 | Perfect mirror | Very high | <0.05 μm | Luxury architecture, art |
Factors That Influence Mirror Surface Quality
Achieving a consistent and flawless mirror finish depends on several key factors:
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Base Material Quality:
Sheets with fewer surface defects result in better reflectivity. -
Polishing Technique:
Multi-stage polishing with proper grit sequence ensures uniform gloss. -
Machine Calibration:
Stable speed and pressure during polishing prevent distortion. -
Operator Expertise:
Skilled technicians can control polishing pressure and direction precisely. -
Clean Environment:
Dust-free finishing areas prevent contamination and scratches.
SAKYSTEEL maintains strict control over each polishing stage to deliver mirror sheets that meet the highest international standards.
Applications of Mirror Stainless Steel Sheets by Grade
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No. 6 and No. 7 Finishes: Ideal for elevator interiors, decorative columns, and wall panels.
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No. 8 Finish: Perfect for architectural exteriors, luxury interiors, and artistic installations.
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Customized Mirror Colors: Through PVD coating, finishes like gold, rose, black, or bronze mirror surfaces can be created for aesthetic diversity.
Mirror stainless steel sheets are widely used in commercial centers, hotels, airports, museums, and high-end residences, enhancing both beauty and functionality.
Maintenance Tips for Mirror Finishes
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Use Non-Abrasive Cleaners: Clean with mild detergents and microfiber cloths.
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Avoid Scratching: Do not use steel wool or rough pads.
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Handle with Care: Keep protective PVC film on until installation.
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Regular Cleaning: Prevent accumulation of dust or fingerprints to maintain reflectivity.
Proper care ensures long-term gloss and corrosion resistance of mirror-finished sheets.
Why Choose SAKYSTEEL Mirror Stainless Steel Sheets
SAKYSTEEL is a trusted stainless steel manufacturer and supplier with years of experience in surface finishing technology. We provide:
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Full range of surface grades (#6, #7, #8)
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Consistent gloss and reflection uniformity
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Customized colors via PVD coating
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Quality inspection reports (Ra measurement, visual tests)
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Secure export packaging with moisture protection
Our mirror finish sheets are used globally in architecture, decorative interiors, and precision fabrication industries, ensuring quality that customers can rely on.
Conclusion
Understanding the surface grades of mirror stainless steel sheets is essential for selecting the right material for your project. The choice between No.6, No.7, and No.8 finishes depends on the desired balance of reflectivity, appearance, and cost.
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Choose No.6 or No.7 for semi-reflective surfaces that hide minor imperfections.
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Choose No.8 when you need a perfect, high-gloss mirror appearance.
Whether for luxury architecture, industrial design, or artistic creation, SAKYSTEEL provides mirror stainless steel sheets that meet global standards of quality and precision.
Post time: Nov-04-2025