Johnston: Amethyst Rockhounding in Providence County, Rhode Island
Updated July 2026
The rock cuts and volcanic outcrops in Johnston, near the Route 6 and Interstate 295 corridor, have produced amethyst and clear to smoky quartz from vugs in the underlying felsic bedrock. It is one of the few inland Rhode Island spots where purple quartz can be found in place rather than as a beach pebble. The exposed cuts make it an accessible stop for seeing the state's crystal-bearing geology. Reported finds include amethyst. Below: coordinates, access notes, nearby spots, and trip-planning links.
Johnston photos
Public image records connected to this spot or its reported material.
Map showing Johnston in Providence County, Rhode Island
Quick details
- Access
- Public area
- County
- Providence County
- State
- Rhode Island
- Nearest road
- Belfield Drive
- Postcode
- 02919
- Coordinates
- 41.83668, -71.52098
Geology at Johnston
This spot sits on Blackstone Group - quartzite, mapped as quartzite that formed roughly 1000 to 540 million years ago. Metamorphic terrain like this typically carries quartz veins and sweats, and weathered crystals tend to end up in the soils and streams below.
- Mapped unit
- Blackstone Group - quartzite
- Age
- 1000–540 Ma (Neoproterozoic)
- Rock types
- quartzite
- Elevation
- 260 ft
Geologic mapping via Macrostrat and the underlying state geological survey maps (CC BY 4.0). Bedrock at the surface can vary within a mapped unit.
Best time to visit Johnston
Best months: March to November. Typical highs run 83°F in midsummer and 38°F in midwinter, with winter lows near 21°F.
Climate normals: NOAA 1991-2020 monthlies, PROVIDENCE station (9 mi away), adjusted for elevation.
Land & collecting status
Generally open to casual rockhounding
Most public-tagged spots sit on BLM, U.S. Forest Service, or other federal land where reasonable hand collecting of common rocks and minerals is allowed. Confirm posted rules and active mining claims before you dig.
Public-land rules vary by agency, season, and field office. The RockHoundR app pulls live BLM, USFS, NPS, and tribal overlays so you can see exactly which agency manages the ground at this spot.
Sources & verification
Spot details combine the public RockHoundR location dataset, normalized mineral labels, agency land-status checks in the app, and community submissions. Coordinates are approximate until verified in the field.
Sources: RockHoundR public spot dataset, app land overlays, and local agency review before each trip.
Found at Johnston
Each chip opens all spots that produce that material; the encyclopedia link opens the full ID and field guide.
Nearby rockhounding spots
Other rockhounding spots within driving distance of Johnston.
- JohnstonProvidence County, Rhode Island · 0 mi awayQuartz
- ProvidenceProvidence County, Rhode Island · 3 mi awayAgate, Chalcedony, Jasper
- North ProvidenceTop pick in Rhode IslandProvidence County, Rhode Island · 8 mi awayBowenite, Quartz, Serpentine
- PawtuxetTop pick in Rhode IslandProvidence County, Rhode Island · 9 mi awayAgate, Carnelian, Amethyst
- Cumberland HillProvidence County, Rhode Island · 10 mi awayAgate, Chalcedony, Jasper
- Sneech PondProvidence County, Rhode Island · 11 mi awayChalcopyrite, Garnet, Magnetite
- Diamond Hill Park, CumberlandTop pick in Rhode IslandProvidence County, Rhode Island · 13 mi awayAmethyst, Quartz, Smoky Quartz
- WarwickTop pick in Rhode IslandKent County, Rhode Island · 14 mi awayCarnelian
Across the state line from Johnston
Johnston is close enough to the Rhode Island border that the next-closest rockhounding spots are in a neighboring state. Worth knowing if you are already on the road.
- MiddlesboroughPlymouth County, Massachusetts · 32 mi awayAgate, Chalcedony
- UnionNortheastern Connecticut Planning Region, Connecticut · 33 mi awayFeldspar, Moonstone, Cordierite
- NorwichSoutheastern Connecticut Planning Region, Connecticut · 35 mi awayCorundum, Sillimanite
- New LondonSoutheastern Connecticut Planning Region, Connecticut · 41 mi awayApatite, Spodumene
- Bolton Lime QuarryWorcester County, Massachusetts · 42 mi awayScapolite
- SterlingWorcester County, Massachusetts · 43 mi awayChalcopyrite, Siderite
Johnston FAQ
Where is Johnston?+
What rocks and minerals can you find at Johnston?+
Is collecting allowed at Johnston?+
What tools should I bring to Johnston?+
When is the best time to visit Johnston?+
How do I get to Johnston?+
More rockhounding in Rhode Island
See all 17 Rhode Island spots →Open Johnston on the map
Use the RockHoundR app for live land overlays, weather, geology, directions, and saved finds.
