Verifying the authenticity of your Grueby pottery involves examining several critical factors. First, look for distinctive Grueby pottery marks, including an impressed 'Grueby Faience Co.' stamp or an artist’s signature. Some authentic pieces, however, may lack visible marks; in such cases, identifying the signature Grueby style glaze—often a rich matte green—and the handcrafted organic motifs is essential. The Grueby Faience Company was known for its attention to detail, so irregularities consistent with hand production are good indicators.

Several factors influence the value of Grueby pottery, including rarity, condition, provenance, and design complexity. Pieces featuring unique forms, exceptional Grueby style glaze variations, or rare Grueby faience tiles typically command higher prices. Grueby pottery marks in excellent condition with clear inscriptions can also enhance value. Provenance plays a vital role—items with documented histories or those featured in significant collections are more sought after. Collectors highly prize pieces designed by prominent artists from the Grueby Faience Company, particularly those with floral relief motifs.

While many authentic Grueby pottery pieces feature identifiable Grueby pottery marks, not all are marked. The Grueby Faience Company occasionally produced works without stamps or signatures, making identification reliant on other factors. Experts typically examine the shape, craftsmanship, and characteristic Grueby style glaze—especially the signature matte green tones—to verify authenticity. Additionally, certain Grueby faience tiles and smaller decorative objects may carry subtle or worn markings due to age.

Proper care is crucial to preserving the beauty and value of your Grueby pottery. Clean pieces gently with a soft, dry cloth to avoid damaging the delicate Grueby-style glaze. Avoid abrasive cleaners and direct contact with water, especially for older items. When displaying, place your Grueby tiles and vases on sturdy surfaces away from high-traffic areas to prevent accidental knocks. Use display stands with cushioned supports to minimize stress on the pottery. Keep pieces out of direct sunlight to avoid fading glaze and away from extreme temperature fluctuations, which can cause cracking.

Grueby Pottery is highly collectible due to its handcrafted artistry, rich matte glazes, and association with the Arts and Crafts movement. The company’s innovative glazing techniques, particularly its signature matte green glaze, set it apart. Pieces designed by notable artists like George Prentiss Kendrick are especially desirable.

Collectors highly value vases with floral relief designs, tiles with intricate patterns, and large sculptural pieces. Rare forms, such as tall vases, unique shapes, and artist-signed works, often fetch premium prices. Items in pristine condition with strong provenance are particularly sought after.

The Grueby Faience Company operated from 1894 to 1913, so all authentic pieces come from this period. Older pieces tend to have thicker glazes and distinct hand-tooling marks. Checking artist signatures, production stamps, and the overall style can help narrow the production time frame.