Mountain Slate Blue 10BB 18/106 is a gray paint color from PPG. It has a hex value of #687788, LRV 18 and a neutral undertone. Its closest cross-brand match is Always Indigo from Behr (nearly identical), with 49 more equivalents across other brands.
Ref. #687788 · 10BB 18/106
Mountain Slate Blue
18%LRV Value
NeutralUndertone
Mountain Slate Blue Technical Profile
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Mountain Slate Blue in Every Brand
The closest equivalent to Mountain Slate Blue in each major paint brand, ranked by how close the match reads. Always verify with a physical sample. How we calculate match accuracy →
PPGMountain Slate Blue
Nearly identical
BehrAlways Indigo
Always Indigo
Behr
Nearly identical
Thundering Clouds
Valspar
Nearly identical
Wharf View
Dunn-Edwards
Very similar
Distance
Sherwin-Williams
Very similar
Blue Depths
Hirshfield's
Very similar
Britannia Blue
Benjamin Moore
Very similar
Blue Depths
Vista Paint
Very similar
Flint Stone
Dutch Boy
Very similar
North Beach Blue
Kilz
Visible difference
Pigeon Blue
RAL
Visible difference
Wine Dark
Farrow & Ball
Visible difference
Comparing these brands? Order peel-and-stick samples of your top matches — Samplize buy 8 peel-and-stick samples, get 2 free.
Recommended Pairings
Colors That Work With Mountain Slate Blue
Timeless pairing with clean white trim and a tonal accent wall
Side Walls
Mountain Slate Blue
#687788
Accent Wall
Tonal Shift
A warm shift that adds depth without clashing.
#7D7CA7
Trim & Molding
Pure White
Crisp white trim for a clean, traditional look.
#FFFFFF
Color Palettes for Mountain Slate Blue
Color harmonies based on color theory — each swatch links to the closest matching paint.
Opposite on the color wheel — creates vibrant contrast
Mountain Slate Blue Room Palettes
Color schemes built around this color — each swatch links to the closest matching paint.
Warm & Inviting
Warm tones with cozy appeal — welcoming and comfortable
Cool & Calm
Cool hues with soft contrast — serene and restful
Bold Contrast
Complementary hues with punch — dynamic and striking
Similar PPG Colors
Other PPG colors close to Mountain Slate Blue.
More gray colors from other brands
Cross-brand colors in the gray family — useful when you want a similar look from a different brand.
Mountain Slate Blue — Frequently Asked Questions
What undertone does Mountain Slate Blue have?
Mountain Slate Blue by PPG has a neutral undertone and sits in the gray color family. The undertone shifts with light — warmer under 2700K bulbs, cleaner and cooler under 4000K daylight — so sample Mountain Slate Blue in your own space before committing.
What colors match Mountain Slate Blue from other brands?
The closest cross-brand equivalents to Mountain Slate Blue are Always Indigo by Behr (a near-identical match), Hypnotic by Behr (a near-identical match), Thundering Clouds by Valspar (a near-identical match) — the best options for getting Mountain Slate Blue's look from a brand your local store carries. Confirm with a physical sample, since sheen and lighting shift the final result.
What is the LRV of Mountain Slate Blue?
Mountain Slate Blue has a Light Reflectance Value (LRV) of 17.9, on a scale where 0 is pure black and 100 is pure white — that makes it a deep, dramatic color best saved for accent walls, dining rooms, and cozy spaces where atmosphere matters more than reflected light.
Explore More with Mountain Slate Blue
Related Reading
How to Match Paint Colors Across Brands
The science behind Delta E and CIEDE2000 — find a Behr equivalent of any Sherwin-Williams shade, or a Benjamin Moore alternative when your store is out of stock.
Understanding Paint Color Undertones
Why Mountain Slate Blue's neutral undertone matters more than its surface color — and how to read undertones in any paint chip.