Trio of bottle-form open-base glass shades

A set of three tear-drop or bottle-form vessels, stylistically consistent with mid-to-late 20th-century decorative art glass. Each piece features a long, narrow neck transitioning into a wide, bulbous body. The surface decoration consists of vertical, slightly swirling striations in a variegated color palette of deep blue, earthy brown, sage green, and white, likely achieved through a pulled-feather or combed glass technique. The interior appears to be lined with a white casing. Notably, the owner reports that these items have no bottoms, which is consistent with their use as hanging lamp globes or pendants rather than traditional vases. No maker's marks, signatures, or labels are visible in the provided image, so any attribution to a specific studio or manufacturer remains a hypothesis. The craftsmanship shows a high degree of uniformity across the set, suggesting professional production. Structurally, the pieces appear intact, though minor surface scuffs or interior dust may be present consistent with age. Identification is based on visual characteristics and user-provided context regarding the open-base construction.

I have examined the provided images and descriptions of this trio of bottle-form glass shades. Based on what I can see, these pieces possess a sophisticated pulled-feather or combed design with a cased white interior, consistent with high-quality studio glass from the late 20th century. The owner reports an open-base construction, which suggests these were intended as pendant light globes rather than stand-alone vases. While the craftsmanship is highly uniform, I cannot verify a specific maker or studio from a photograph as no signatures or labels are visible. If these were produced by a recognized studio like Quezal or a contemporary artisan such as Lundberg Studios, the value would align with the $450-$750 range for the set. However, without a physical inspection or provenance, this attribution remains a hypothesis. My estimate assumes the pieces are professional studio glass; should they be identified as mass-produced commercial reproductions, the value would likely drop to $75-$150. A physical examination is required to check for micro-stamping, glass density, and pontil characteristics to differentiate between artisanal work and high-volume manufacturing. The current market for mid-century style decorative lighting remains stable, with significant demand for complete sets in good condition. To provide a more precise valuation, I would need to observe the items in person to rule out surface abrasions or heat-related stress fractures that are not visible in the images. Authenticity and specific maker attribution would require verification of documentation or comparison against known catalogs by a specialist.