The key to determining the authenticity of quartz stone countertops lies in practical testing driven by scientific principles and intuitive identification of material characteristics, combined with common pitfalls in the consumer market for comprehensive screening.

White vinegar drip test: Take a small amount of edible white vinegar and drip it onto the edge or back of the table, let it stand for 5 minutes. Authentic quartz stone is dense and pore free, without any bubbles or discoloration reactions; Poor quality products often contain calcium carbonate (granite), which will cause severe foaming and leave sticky residue when exposed to acetic acid. The chemical reaction is:

Key scratch test: Use a regular key to lightly scratch 2-3 times in a concealed area. The genuine product has a Mohs hardness of 6-7 on quartz sand, leaving only black metal scratches that can be wiped clean with a damp cloth; Poor quality products may have insufficient hardness, resulting in white powdery scratches or deep concave marks, indicating a quartz content of less than 85%, mixed with calcium powder or resin.

Soy sauce penetration test: Drop a drop of dark soy sauce or soy sauce, let it stand for 20 minutes, and then wipe it with a damp cloth. The genuine product has a water absorption rate of less than 0.2%, with a clean surface and no color bleeding; Poor quality products, due to their loose structure, will leave permanent yellow brown marks, which are prone to mold growth and difficult to remove stains in the future.

Lighter burning test: Use the outer flame of the lighter to burn the edge of the tabletop for 3-5 seconds, and observe after cooling. Authentic resin content ≤ 10%, only slightly carbonized on the surface, can be easily wiped clean, and has no odor; Poor quality resin exceeding the standard will turn yellow, sticky, and emit a pungent plastic smell, and is prone to deformation and cracking when exposed to heat for a long time.

✅ All tests must be conducted at the edges, corners, or back to avoid damaging the aesthetic appearance of the tabletop. If the merchant refuses to cooperate with the testing, it is highly likely that the product is of poor quality or counterfeit.

Identification of material and process characteristics:

Quartz content: Genuine quartz sand accounts for ≥ 90%, while high-quality products can reach over 93%; Less than 85% of products are often impersonated as "granite", with low strength and easy cracking.

Thickness standard: For qualified products with a thickness of ≥ 15mm, it is recommended to use a thickness of 20mm or more; 10-13mm is a poor quality threshold with severely insufficient load-bearing capacity, especially in suspended areas where it is prone to breakage.

Back label: Legitimate products have clear brand spray codes, production batch numbers, and anti-counterfeiting codes; If there are three no products, there will be no labeling, or the printing will be blurry or the handwriting will fall off.

Particle distribution: The particles on both sides of the genuine product are uniform and delicate, without impurities; The front of the inferior product is polished delicately, while the back is rough and messy, making it a low-quality product formed by casting.

Touch and smell: The genuine product feels cold to the touch, with a natural stone like coldness; Poor quality products are as warm as plastic and often accompanied by a pungent odor of formaldehyde or resin, which does not meet environmental standards.

⚠️ Linyi Consumer Warning: There are a large number of low-priced countertops in the local market priced at "200-500 yuan/linear meter", which are actually "fake quartz stones" mixed with calcium carbonate and resin. After 6-12 months of use, there will be color bleeding, cracking, and deformation, making it difficult to protect rights. It is recommended to prioritize choosing legitimate brands such as Zhongqi New Materials and Weiyang Stone with CMA testing reports.

Core principles for purchasing:

The contract must specify in writing that the quartz sand content is ≥ 90%, the thickness is ≥ 20mm, and it complies with JG/T 463-2014 standards. Verbal promises are invalid.

Request and verify the CMA certification test report, confirming that it includes three core indicators: bending strength ≥ 34MPa, water absorption ≤ 0.2%, and pollution resistance (no color leakage in soy sauce for 24 hours).

Reserve a 5cm x 5cm corner material before installation as a physical basis for acceptance and rights protection.