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<\/p>\nGranite Inspection Procedure & Key Points
\nThis document outlines the standard procedure and critical focus areas for inspecting granite slabs and tiles before shipment or upon receipt.<\/p>\n
I.?Pre-Inspection Preparation
\nDocument Review:<\/p>\n
Purchase Order (PO): Verify quantity, dimensions, thickness, finish, and product name.<\/p>\n
Quarry Block Report: Confirm the origin of the stone batch.<\/p>\n
Packing List: Cross-check against the actual shipment.<\/p>\n
Tools & Environment:<\/p>\n
Tools: Measuring tape\/caliper, straightedge, square, moisture meter, digital colorimeter (if color matching is critical), UV lamp (for resin detection), and a bright light source.<\/p>\n
Environment: Inspection must be conducted in a well-lit area, preferably under natural daylight or bright, neutral white light to accurately assess color and finish.<\/p>\n
II. Inspection Procedure & Key Points
\nThe inspection should be systematic, covering visual, dimensional, and physical characteristics.<\/p>\n
A. Visual Inspection (Surface Quality)<\/p>\n
Color & Pattern Consistency:<\/p>\n
Focus: Compare slabs\/tiles from the same batch. There should be no drastic color variation from the approved sample.<\/p>\n
Key Point: Natural variation is expected, but it should be within an acceptable range as per the project requirements.<\/p>\n
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Finishing Quality:<\/p>\n
Polished: Must have a uniform, high-gloss mirror finish without hazy or dull areas.<\/p>\n
Honed: Should have a smooth, satin-uniform matte finish.<\/p>\n
Flamed\/Bush-Hammered: Texture should be consistent across the entire surface.<\/p>\n
Surface Defects:<\/p>\n
Cracks & Fissures: Distinguish between superficial fissures (natural, usually acceptable) and structural cracks (deep, often unacceptable).<\/p>\n
Chips & Pits: Check for small missing pieces on the surface, especially on edges and corners.<\/p>\n
Stains: Look for oil, rust, or chemical stains that cannot be removed.<\/p>\n
Discoloration: Check for blotches or areas that are significantly darker\/lighter.<\/p>\n
Veining & Markings:<\/p>\n
Focus: Ensure the natural veining is as expected. Check for ugly or concentrated spots of minerals that affect aesthetics.<\/p>\n
B. Structural & Dimensional Inspection<\/p>\n
Thickness:<\/p>\n
Focus: Measure thickness at multiple points (center and all four corners) using a caliper.<\/p>\n
Key Point: Thickness must be consistent and within the tolerance specified (e.g., +\/- 1mm for 2cm slab).<\/p>\n
Dimensions:<\/p>\n
Focus: For tiles, check length, width, and diagonal dimensions.<\/p>\n
Key Point: Ensure consistency to avoid lippage (uneven edges) during installation.<\/p>\n
Squareness & Flatness:<\/p>\n
Squareness: Use a carpenter’s square to check if corners are 90 degrees.<\/p>\n
Flatness: Place a long straightedge on the surface. Check for any gaps indicating warpage or bowing.<\/p>\n
C. Resin & Filling Inspection<\/p>\n
Purpose: Most granites are resin-treated to fill minor pits and fissures and enhance the polish.<\/p>\n
Inspection:<\/p>\n
Visual: Look for areas where the resin has a different gloss, color, or transparency than the natural stone. It should be invisible.<\/p>\n
UV Light: Use an ultraviolet lamp. Resin-filled areas will often fluoresce differently than the natural stone, revealing the extent and quality of the repair.<\/p>\n
Key Point: Excessive or poorly matched resin is a major defect.<\/p>\n
D. Physical Condition & Packing<\/p>\n
Edges & Corners:<\/p>\n
Focus: Inspect for chipping or damage on all edges and corners, which are highly vulnerable.<\/p>\n
Moisture Content:<\/p>\n
Focus: Use a moisture meter. High moisture content can lead to efflorescence (white salt deposits) after installation.<\/p>\n
Key Point: Slabs should be dry, especially if they are resin-treated.<\/p>\n
Packing:<\/p>\n
Focus: Check if slabs\/tiles are properly packed with sturdy crates, adequate separators (e.g., foam or cardboard between slabs), and well-secured to prevent movement and damage during transit.<\/p>\n
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III. Defect Classification & Reporting
\nMajor Defect: Structural cracks, deep stains, excessive warpage, or any flaw that makes the piece unusable for its intended purpose. Result: REJECT the piece.<\/p>\n
Minor Defect: Small, superficial pits, minor color variation, or small edge chips that can be repaired or are acceptable for the project. Result: Document and negotiate a discount or repair.<\/p>\n
AQL (Acceptable Quality Level): For large shipments, use a statistical sampling plan (like AQL) to determine how many pieces to inspect and the maximum number of allowable defects.<\/p>\n
Final Report: The inspection report should include photos of all defects, measurements, and a clear summary of accepted, rejected, and questionable pieces<\/p>\n","protected":false},"excerpt":{"rendered":"