Gatewayite is a local variety of chert or chalcedony found near Gateway, Colorado. It typically presents as massive, dull-to-waxy material that is frequently used by lapidaries for polishing and cabochon making due to its high silica content and durability.

Hardness

Mohs

Luster

Waxy

Streak

White

Transparency

Translucent

mineralcommonQuartz family

Gatewayite

Hardness: 7
Luster: Waxy
Streak: White
Transparency: Translucent

No image

Is this gatewayite?

5-step field check

Run through these checks against the specimen in your hand. The more boxes tick, the more confident the ID.

1
Test the hardness
Try to scratch gatewayite with a known reference. Gatewayite sits at Mohs 7, softer than the next harder reference, harder than the previous one.
2
Check the streak
Drag the specimen across an unglazed porcelain plate. Gatewayite leaves a white streak.
3
Read the luster
Hold the specimen under a strong light. Gatewayite typically shows a waxy luster.
4
Match the color range
Compare against the expected color range: white, gray, brown.
5
Look at form & habit
Crystal system: trigonal. Typical habit: massive.

Often confused with

Gatewayite vs. its common look-alikes, and how to tell them apart in the field.

Often found alongside gatewayite

Minerals reported to co-occur with gatewayite. Spotting these in float or country rock is a strong cue you are in the right ground.

All properties

Chemical formula: SiO₂
Mohs hardness: 7
Density: 2.65 g/cm³
Colors: White Gray Brown
Streak: White
Luster: Waxy
Transparency: Translucent
Crystal system: Trigonal
Crystal habit: Massive
Cleavage: None
Rarity: Common
Uses: Lapidary, Collector
Host rock: Sedimentary Formations
Typical price: $5-30 for rough specimens

Where rockhounds find gatewayite

Classic worldwide localities

Gateway, Colorado, USA

Field-hunting tip

Look in sedimentary formations country, the host setting where gatewayite typically forms. If you start seeing quartz, calcite, barite in float, you are in the right ground. Field specimens usually show a massive habit, so train your eye for that shape before scanning the outcrop.

Common questions

How do you identify gatewayite?+

Mohs hardness is 7. It typically shows a waxy luster. The streak is white. Common colors include white, gray, brown.

Where is gatewayite found?+

Notable localities include Gateway, Colorado, USA.

How much is gatewayite worth?+

Typical asking prices fall in the range of $5-30 for rough specimens. Quality, size, and provenance can move individual specimens well outside that range.

What rocks look like gatewayite?+

Gatewayite is most often confused with Flint Nodules, Chalcedony, Jasper. A quick hardness test and a streak check separate the look-alikes faster than color alone.

What minerals are found with gatewayite?+

Gatewayite commonly co-occurs with Quartz, Calcite, Barite. Spotting any of these in float or country rock is a useful trip signal.

What kind of rock does gatewayite form in?+

Gatewayite typically forms in sedimentary formations. Working float back to the host body is the standard way to chase a fresh occurrence.

What is gatewayite used for?+

Gatewayite is used in lapidary, collector.

Find gatewayite on the map

RockHoundR shows mapped rockhounding spots, access rules, and lets you log every find.