SP 1520 Necef

Product Code: SP 1520 – Necef
Category: Crystal Glazes
Recommended Firing Range: 1200–1220°C
Form: Supplied in liquid form in 175 g, 500 g, and 1000 g packages.

Product Features

• The glaze has a dirty white base and forms pearl-white crystals on the surface.
• Overall, the glaze is transparent, while the crystal particles are opaque.
• The base remains glossy; crystal regions may appear matte.
• In 2–3 coat applications or more, the glaze may show running tendencies depending on thickness.
• Higher risk of glaze crazing (surface cracking).
• Free of toxic substances.

Note: In crystal glazes, acid resistance depends on the density and distribution of surface crystals. Dense crystal coverage reduces acid resistance, whereas balanced and controlled crystal distribution preserves the glass structure, resulting in higher resistance. Therefore, chemical durability is directly influenced by the surface glaze and the user’s production process.

 

Application Methods

Important: To support crystal formation, both thin and thick applications should be used on the same surface. Excessive thickness across the entire surface may cause dense crystals to merge, covering the surface completely, producing a matte and slightly rough “crystal matte” appearance. Very thin coverage may result in weak crystal growth.

• For vertical surfaces, apply thicker layers at higher points and gradually thin downward.
• On horizontal surfaces, alternating thin-thick areas help crystals distribute evenly.
• This ensures each product develops a unique crystal pattern.
• Crystal glazes perform best with spray (pistol) or dipping methods.
• Brush applications: 1–3 coats on the same surface.
• Spray or dipping: add approximately 5–30% water to adjust density.
• Recommended Baumé range: 45–55.

 

Testing Recommendation

• First-time users should prepare test tiles under their own kiln conditions and application methods, both vertical and horizontal.
• In the product image, the glaze was applied on BNC 1200 white porcelain clay. Its transparent nature may produce different results on colored clays.
• When combining with other artistic glazes, testing is recommended to prevent defects.

 

Care and Cleaning

• Dishwasher use may expose the glaze to high-temperature chemical solutions, potentially causing matting or changes in artistic effects.

 

Safety

• Personal protective equipment is recommended during application.
• Keep glazes away from fire and open flames during use.
• Children should apply under supervision.

 

Storage

• Store in airtight conditions, away from direct sunlight.
• If stored for long periods, the glaze may begin to dry; add water, mix thoroughly, and sieve before use.
• After opening, over time, brushing agents, stabilizers, and antibacterial additives may lose effectiveness. This usually does not affect firing results but may influence application performance (harder application or pre-firing surface cracking). Contact us for recommendations if this occurs.