Thermal retention estimates for STŌN coasters are based on internal testing using a standard 300 ml ceramic mug filled with water at 85°C, placed on a coaster pre-heated to 40°C in a controlled environment at 22°C ambient temperature. Actual retention time depends on mug material, beverage volume, ambient temperature, airflow conditions, and surface contact quality. Results may vary between service environments.
Preheat time of under 5 minutes was measured using the STŌN Heat Column at default settings with coasters starting from room temperature (22°C). Preheat duration may vary when using third-party warming cabinets, depending on cabinet wattage, internal airflow, load capacity, and starting temperature of the coasters.
Energy consumption of the STŌN Heat Column (estimated under 1.5 kWh per full service day) is based on continuous operation during a simulated 10-hour service cycle at 40°C set point. Actual consumption depends on ambient temperature, frequency of door openings, number of coasters loaded, and voltage stability. Energy costs are estimated using average US commercial electricity rates and may differ by region.
Quartzite hardness rating of Mohs 7 refers to the mineral hardness of the Taj Mahal Quartzite variety used in standard STŌN coasters. Hardness may vary slightly between individual slabs due to natural mineral composition differences. Mohs scale measures scratch resistance only and does not indicate resistance to impact, chipping from drops, or structural failure under point loads.
Zero porosity claims are based on water absorption testing per ASTM C97 standards, yielding results below 0.1%. "Zero porosity" is used for communication purposes and reflects functionally non-absorbent behavior under normal hospitality use. Microscopic porosity may exist at geological scale but does not affect stain resistance or hygiene performance in service conditions.
Acid resistance of the quartzite surface was evaluated through exposure testing with common food-service substances including coffee, red wine, lemon juice, and vinegar over a 24-hour contact period. No visible staining or etching was observed. Results apply to honed-finish quartzite only. Prolonged exposure to industrial-grade acids or chemicals not typical in food service has not been tested.
Thermowood base specifications reflect properties of thermally modified European ash treated under the ThermoWood process at 190–215°C. Dimensional stability, moisture resistance, and thermal conductivity values are based on manufacturer-published data and may vary between wood batches, treatment facilities, and grain orientation. Thermowood is not waterproof and should not be submerged or placed in dishwashers.
Dishwasher safety applies to the quartzite stone insert only. The Thermowood base must not be placed in a dishwasher, submerged in water, or exposed to prolonged moisture. Cleaning the wood base with a damp cloth is recommended. Failure to follow care instructions may result in warping, discoloration, or degradation of the wood finish.
Custom laser engraving is performed using CO2 or fiber laser equipment at 0.1–0.3 mm depth on the quartzite surface. Logo reproduction accuracy depends on source file resolution, design complexity, and contrast requirements. Fine details below 0.5 mm line width may not reproduce clearly on natural stone surfaces due to grain variation. Color fill options, if applied, may wear over time with repeated cleaning cycles.
Product photography, 3D renders, and color representations on this website are based on pre-production samples and digital assets. Natural stone varies in color, veining, and texture between slabs and individual units. No two STŌN coasters are identical. Variations in appearance are inherent to natural materials and are not considered defects.
Compatibility with warming cabinets refers to standard commercial plate warmers capable of maintaining a stable 40°C set point. STŌN does not certify, endorse, or guarantee performance with any specific third-party warming cabinet brand. Users are responsible for verifying temperature accuracy and stability of their own equipment.
The STŌN Heat Column uses infrared heating elements to transfer energy directly to stone coasters. Infrared performance depends on emitter positioning, coaster placement within the rack, and unit maintenance. Temperature uniformity across rack positions was measured during factory testing and may differ slightly under field conditions.
Weight and dimensional specifications are nominal values based on production targets. Individual coasters may vary within stated tolerances (±0.5 mm diameter, ±0.5 mm thickness) due to natural stone cutting and finishing processes. Weight may vary by ±15 g depending on quartzite density within a given slab.
Estimated unit costs, pricing tiers, and volume discounts referenced on this website or in sales materials are subject to change without notice based on raw material availability, fabrication costs, shipping rates, and exchange rates. Final pricing is confirmed at the time of order and may differ from published estimates.
Warranty coverage, if applicable, covers manufacturing defects in materials and workmanship under normal hospitality use. Warranty does not cover damage from drops onto hard surfaces, use of abrasive cleaning agents on the wood base, exposure to temperatures exceeding 100°C, unauthorized modifications, or normal wear patterns such as patina development on the wood finish.
Shipping times and delivery estimates reflect typical carrier performance for domestic US shipments. International orders, custom-branded orders, and large-volume orders may require additional lead time. Conditions such as customs processing, carrier delays, material availability, or peak seasonal demand may extend delivery windows beyond stated estimates.
Environmental and sustainability claims reflect STŌN's design intent, including the use of natural materials, zero-energy operation at point of service, and product longevity. Actual environmental impact depends on raw material sourcing, manufacturing energy use, shipping distances, and end-of-life disposal practices. Claims may be updated as supply chain practices evolve.
The recommendation of 1.5× coasters per seat is a general guideline based on typical café and restaurant service rotation patterns. Actual requirements depend on table turnover rate, service style, peak hours, and warming cabinet capacity. STŌN representatives can assist with capacity planning for specific operations upon request.
STŌN®, STŌN Heat Column™, and all associated product names, logos, and design elements are trademarks of STŌN. Unauthorized reproduction, distribution, or use of any content, imagery, or intellectual property from this website is prohibited without prior written consent.
Third-party services referenced on this website, including payment processors, analytics platforms, and shipping carriers, operate under their own terms, privacy policies, and data handling practices. STŌN does not control how these external services process data after transfer.