When evaluating pure fabrics (such as 100% cotton, silk, or linen), you must prioritize Fiber Purity Verification through lab reports to ensure no synthetic blends are present. Key metrics include Thread Count (TC) or Grams per Square Meter (GSM) to determine thickness and durability. For apparel, check the Yarn Count (e.g., 40s, 60s); higher numbers indicate a finer, softer weave. Additionally, verify Color Fastness to Washing and Light (Grade 4 or above is standard for premium exports) and Shrinkage Rates, which should ideally be below 3% for pre-shrunk high-quality textiles.