Lace Obsidian
Volcanic glass (silica-rich, ~70-75% SiO2, amorphous)
Black volcanic glass laced with delicate web-like veins of contrasting color, formed by flow banding and fine crystallization.
- Mohs hardness
- 5-5.5
- Color
- Black with fine reddish, brown, or pale lace-like veining
- Type
- igneous
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Overview
Lace Obsidian is a trade name for obsidian displaying delicate, interlacing veins or web-like patterns of contrasting color, often reddish-brown, cream, or gray, threaded through a dark glassy body. It overlaps with names like midnight lace and spiderweb obsidian.
The base is natural volcanic glass. The lace patterns arise from flow banding frozen into the lava combined with fine zones of iron staining or partial crystallization.
It is valued as an ornamental and collector stone for its intricate, almost painterly markings.
Formation & geology
Lace Obsidian originates as silica-rich lava that cools too quickly to crystallize, forming glass. As the viscous lava flowed before solidifying, it developed flow banding, thin layers and swirls of slightly differing composition or iron content.
When these bands are thin, intertwined, and emphasized by iron oxide staining or incipient crystallization, they create the lacy network. Later oxidation can pick out veins in red and brown. The result records the dynamic motion of the lava just before it froze into glass.
How to identify it
Look for obsidian's vitreous luster, conchoidal fracture, sharp edges, hardness ~5-5.5, and white streak. Lace Obsidian specifically shows fine, branching, web- or lace-like veins of contrasting color crossing a dark base.
Hold polished pieces to light to see the delicate banding; the patterns are internal, not surface coatings.
Look-alikes: spiderweb jasper/agate (harder at ~6.5-7, waxy not glassy), dendritic agate (tree-like manganese inclusions in translucent chalcedony), and crazy lace agate (banded chalcedony). Obsidian's glassy fracture and lower hardness set it apart.
Uses & significance
Lace Obsidian is fashioned into cabochons, beads, tumbled stones, and decorative carvings, where its intricate veining is showcased. It is a popular but inexpensive ornamental material.
Like other obsidian, it polishes brilliantly and was historically used for cutting tools owing to its sharp fracture edges.
Metaphysically it is marketed for protection and clarity, claims that are spiritual rather than scientific.
Frequently asked questions
What creates the lace pattern in Lace Obsidian?
Thin flow bands frozen into the lava, often highlighted by iron oxide staining or fine crystallization, form the interlacing web-like veins.
Is Lace Obsidian the same as midnight lace obsidian?
They are very similar trade names; midnight lace typically emphasizes a very dark base with fine lacy banding visible against light. Both are patterned obsidian.
How can I distinguish it from lace agate?
Lace agate is harder (~6.5-7), waxy, and often translucent banded chalcedony, while Lace Obsidian is glassy with conchoidal fracture and a hardness near 5-5.5.
Is Lace Obsidian dyed?
Reputable lace obsidian is naturally patterned by flow banding and iron staining, not dyed.
Lace Obsidian guides
In-depth guides for identifying, valuing, and understanding Lace Obsidian.
