diff --git a/CONTRIBUTING.md b/CONTRIBUTING.md
index 8dc708b..b6e37af 100644
--- a/CONTRIBUTING.md
+++ b/CONTRIBUTING.md
@@ -87,10 +87,20 @@ npm install
 
 ### Project Structure
 
-All distribution files are contained in the `src` folder. The `tests` folder contains the scripts used to verify the matchers work as designed (using the matchers themselves!)
+All distribution files are contained in the `src` folder. The `tests` folder contains the scripts used to verify the matchers work as designed (using the matchers themselves!).
+
+`core` contains the functions that `matchers` use.
 
 ```
 ├── src
+│   ├── core
+│   │   ├── boundingBoxes
+│   │   ├── coordinates
+│   │   ├── features
+│   │   ├── featureCollections
+│   │   ├── functional
+│   │   ├── geometries
+│   │   └── geometryCollections
 │   ├── matchers
 │   │   ├── boundingBox
 │   │   ├── coordinate
diff --git a/src/core/coordinates/valid2DCoordinate.js b/src/core/coordinates/valid2DCoordinate.js
new file mode 100644
index 0000000..de20240
--- /dev/null
+++ b/src/core/coordinates/valid2DCoordinate.js
@@ -0,0 +1,39 @@
+/**
+ * A helper function used to verify a coordinate has appropriate longitude and latitude values.
+ *
+ * @memberof Core.Coordinates
+ * @param {GeoJSON-Coordinate} coordinate A WGS-84 array of [longitude, latitude]
+ * @returns {boolean} True if a valid 2D GeoJSON coordinate. If invalid, it will throw an error.
+ * @throws {Error} Input must be an array of only two elments
+ * @throws {RangeError} Longitude must be a number between -180 and 180
+ * @throws {RangeError} Latitude must be a number between -90 and 90
+ */
+function valid2DCoordinate(coordinate) {
+    if (!Array.isArray(coordinate) || coordinate.length !== 2) {
+        throw new Error('Input must be an array of only two elments.')
+    }
+
+    if (
+        typeof coordinate[0] !== 'number' ||
+        coordinate[0] < -180 ||
+        coordinate[0] > 180 ||
+        // eslint-disable-next-line no-self-compare
+        coordinate[0] !== coordinate[0] // Accounts for NaN
+    ) {
+        throw new Error('Longitude must be a number between -180 and 180.')
+    }
+
+    if (
+        typeof coordinate[1] !== 'number' ||
+        coordinate[1] < -90 ||
+        coordinate[1] > 90 ||
+        // eslint-disable-next-line no-self-compare
+        coordinate[1] !== coordinate[1] // Accounts for NaN
+    ) {
+        throw new Error('Latitude must be a number between -90 and 90.')
+    }
+
+    return true
+}
+
+exports.valid2DCoordinate = valid2DCoordinate
diff --git a/src/core/coordinates/valid3DCoordinate.js b/src/core/coordinates/valid3DCoordinate.js
new file mode 100644
index 0000000..5f6b293
--- /dev/null
+++ b/src/core/coordinates/valid3DCoordinate.js
@@ -0,0 +1,30 @@
+const { valid2DCoordinate } = require('./valid2DCoordinate')
+
+/**
+ * A helper function used to verify a coordinate has appropriate longitude, latitude, and altitude values.
+ *
+ * @memberof Core.Coordinates
+ * @param {GeoJSON-Coordinate} coordinate A WGS-84 array of [longitude, latitude, alititude]
+ * @returns {boolean} True if a valid 3D GeoJSON coordinate. If invalid, it will throw an error.
+ * @throws {Error} Input must be an array of only three elments
+ * @throws {Error} Altitude value must be numeric
+ */
+function valid3DCoordinate(coordinate) {
+    if (!Array.isArray(coordinate) || coordinate.length !== 3) {
+        throw new Error('Input must be an array of only three elments.')
+    }
+
+    // The first two elements have to match the same validity requirements as a 2D coordinate.
+    // Reuse the logic from that function.
+    valid2DCoordinate([coordinate[0], coordinate[1]])
+
+    // eslint-disable-next-line no-self-compare
+    if (typeof coordinate[2] !== 'number' || coordinate[2] !== coordinate[2]) {
+        // Self compare accounts for NaN
+        throw new Error('Altitude value must be numeric.')
+    }
+
+    return true
+}
+
+exports.valid3DCoordinate = valid3DCoordinate
diff --git a/src/matchers/coordinates/isValid2DCoordinate.js b/src/matchers/coordinates/isValid2DCoordinate.js
index ae66bc8..27a1f49 100644
--- a/src/matchers/coordinates/isValid2DCoordinate.js
+++ b/src/matchers/coordinates/isValid2DCoordinate.js
@@ -1,40 +1,4 @@
-/**
- * A helper function used to verify a coordinate has appropriate longitude and latitude values.
- *
- * @memberof Core.Coordinates
- * @param {GeoJSON-Coordinate} coordinate A WGS-84 array of [longitude, latitude]
- * @returns {boolean} True if a valid 2D GeoJSON coordinate. If invalid, it will throw an error.
- * @throws {Error} Input must be an array of only two elments
- * @throws {RangeError} Longitude must be a number between -180 and 180
- * @throws {RangeError} Latitude must be a number between -90 and 90
- */
-function valid2D(coordinate) {
-    if (!Array.isArray(coordinate) || coordinate.length !== 2) {
-        throw new Error('Input must be an array of only two elments.')
-    }
-
-    if (
-        typeof coordinate[0] !== 'number' ||
-        coordinate[0] < -180 ||
-        coordinate[0] > 180 ||
-        // eslint-disable-next-line no-self-compare
-        coordinate[0] !== coordinate[0] // Accounts for NaN
-    ) {
-        throw new Error('Longitude must be a number between -180 and 180.')
-    }
-
-    if (
-        typeof coordinate[1] !== 'number' ||
-        coordinate[1] < -90 ||
-        coordinate[1] > 90 ||
-        // eslint-disable-next-line no-self-compare
-        coordinate[1] !== coordinate[1] // Accounts for NaN
-    ) {
-        throw new Error('Latitude must be a number between -90 and 90.')
-    }
-
-    return true
-}
+const { valid2DCoordinate } = require('../../core/coordinates/valid2DCoordinate')
 
 // eslint-disable-next-line jsdoc/require-returns
 /**
@@ -81,12 +45,11 @@ function isValid2DCoordinate(coordinateArray) {
     }
 
     try {
-        valid2D(coordinateArray)
+        valid2DCoordinate(coordinateArray)
     } catch (err) {
         return { pass: false, message: () => failMessage(err.message) }
     }
     return { pass: true, message: () => passMessage }
 }
 
-exports.valid2D = valid2D
 exports.isValid2DCoordinate = isValid2DCoordinate
diff --git a/src/matchers/coordinates/isValid3DCoordinate.js b/src/matchers/coordinates/isValid3DCoordinate.js
index 98ad05e..c08c09b 100644
--- a/src/matchers/coordinates/isValid3DCoordinate.js
+++ b/src/matchers/coordinates/isValid3DCoordinate.js
@@ -1,30 +1,4 @@
-const { valid2D } = require('./isValid2DCoordinate')
-/**
- * A helper function used to verify a coordinate has appropriate longitude, latitude, and altitude values.
- *
- * @memberof Core.Coordinates
- * @param {GeoJSON-Coordinate} coordinate A WGS-84 array of [longitude, latitude, alititude]
- * @returns {boolean} True if a valid 3D GeoJSON coordinate. If invalid, it will throw an error.
- * @throws {Error} Input must be an array of only three elments
- * @throws {Error} Altitude value must be numeric
- */
-function valid3D(coordinate) {
-    if (!Array.isArray(coordinate) || coordinate.length !== 3) {
-        throw new Error('Input must be an array of only three elments.')
-    }
-
-    // The first two elements have to match the same validity requirements as a 2D coordinate.
-    // Reuse the logic from that function.
-    valid2D([coordinate[0], coordinate[1]])
-
-    // eslint-disable-next-line no-self-compare
-    if (typeof coordinate[2] !== 'number' || coordinate[2] !== coordinate[2]) {
-        // Self compare accounts for NaN
-        throw new Error('Altitude value must be numeric.')
-    }
-
-    return true
-}
+const { valid3DCoordinate } = require('../../core/coordinates/valid3DCoordinate')
 
 // eslint-disable-next-line jsdoc/require-returns
 /**
@@ -74,12 +48,11 @@ function isValid3DCoordinate(coordinateArray) {
     }
 
     try {
-        valid3D(coordinateArray)
+        valid3DCoordinate(coordinateArray)
     } catch (err) {
         return { pass: false, message: () => failMessage(err.message) }
     }
     return { pass: true, message: () => passMessage }
 }
 
-exports.valid3D = valid3D
 exports.isValid3DCoordinate = isValid3DCoordinate