Identification guide · Minerals
How to Identify Howlite
Howlite typically shows a porcelain-white to gray, chalky surface crossed by irregular gray to black veins, giving it a superficial resemblance to turquoise, especially once dyed. Luster is dull to slightly waxy, streak is white, and hardness is about 3.5, softer than true turquoise. It shows no obvious cleavage and breaks with an uneven fracture. Because dyeing is so common, checking whether color sits evenly in the veining rather than saturating the whole stone is a useful field check.
Howlite identification checklist
| Color | White with gray veining | Look at a clean, dry surface in daylight. Color zoning, banding or spots are as diagnostic as the hue. |
|---|---|---|
| Luster | Subvitreous to dull | Fresh surfaces shine like glass; a dull surface usually means weathering, so chip or wet a corner. |
| Transparency | Opaque | Hold a thin edge up to a bright light and note whether light passes through. |
| Mohs hardness | 3–3.5 | A copper coin (Mohs 3.5) scratches it, but a fingernail does not. |
| Streak | White | Drag a corner across unglazed porcelain (the back of a bathroom tile) and check the powder color. |
| Cleavage | None | |
| Fracture | Irregular to uneven | |
| Specific gravity | 2.45–2.6 | Ordinary rock-like heft (specific gravity about 2.5250000000000004), similar to quartz. |
| Crystal system | Monoclinic |
Howlite look-alikes and how to tell them apart
Both sit near Mohs 3–3.5, so a scratch test alone will not separate them. Lean on luster, streak and heft instead. Howlite vs Calcite →
Howlite is harder (Mohs 3–3.5) than Alabaster (Mohs 1.5–2), so Howlite will scratch Alabaster and not the other way round. A fingernail (Mohs 2.5) scratches it easily. Howlite vs Alabaster →
Both sit near Mohs 3–3.5, so a scratch test alone will not separate them. Lean on luster, streak and heft instead. Howlite vs Gibbsite →
Howlite is harder (Mohs 3–3.5) than Bauxite (Mohs 1–3), so Howlite will scratch Bauxite and not the other way round. A fingernail (Mohs 2.5) scratches it easily.
Howlite identification FAQ
How can you tell if a rock is Howlite?
Check the color (white with gray veining), the subvitreous to dull luster, a Mohs hardness of 3–3.5 and a white streak. Photographing it with the StoneSnap app gives a match in seconds.
What is the hardness of Howlite?
Howlite has a Mohs hardness of 3–3.5. A copper coin (Mohs 3.5) scratches it, but a fingernail does not.
What is the difference between Howlite and Calcite?
Howlite (Mohs 3–3.5, subvitreous to dull luster) and Calcite (Mohs 3, vitreous luster) look alike, but hardness, streak and heft usually separate them. See the full Howlite vs Calcite comparison for a side-by-side table.
Is Howlite worth anything?
Entry-level Howlite specimens sell for around $2, typical collector pieces about $20, and premium examples $150 or more depending on size, quality and locality.
What color is Howlite?
Howlite is most often white with gray veining. Color varies with impurities and locality, so confirm with hardness and luster rather than color alone.
