For type "MultiPolygon", the "coordinates" member must be an array of Polygon coordinate arrays.
See also
Other geo types:
Feature,
FeatureCollection,
GeometryCollection,
LineString,
MultiLineString,
MultiPoint,
Point,
Polygon,
geojson-types
Examples
'{
"type": "MultiPolygon",
"coordinates": [
[[[102.0, 2.0], [103.0, 2.0], [103.0, 3.0], [102.0, 3.0], [102.0, 2.0]]],
[[[100.0, 0.0], [101.0, 0.0], [101.0, 1.0], [100.0, 1.0], [100.0, 0.0]],
[[100.2, 0.2], [100.8, 0.2], [100.8, 0.8], [100.2, 0.8], [100.2, 0.2]]]
]
}'
#> [1] "{\n \"type\": \"MultiPolygon\",\n \"coordinates\": [\n [[[102.0, 2.0], [103.0, 2.0], [103.0, 3.0], [102.0, 3.0], [102.0, 2.0]]],\n [[[100.0, 0.0], [101.0, 0.0], [101.0, 1.0], [100.0, 1.0], [100.0, 0.0]],\n [[100.2, 0.2], [100.8, 0.2], [100.8, 0.8], [100.2, 0.8], [100.2, 0.2]]]\n ]\n}"