This is what the gilded blackstone's json looks like,i did change what item it drops with silk touch and what item it usually drops.
Basically, depending on the fortune level the gold nugget has a different chance to drop (from 10% at nothing to 100% at fortune 3).
Changing anything about the gold nugget's functions/conditions makes the item no longer be random, and instead give the first one even if i add weight to them
{
"type": "minecraft:block",
"pools": [
{
"rolls": 1,
"entries": [
{
"type": "minecraft:alternatives",
"children": [
{
"type": "minecraft:item",
"conditions": [
{
"condition": "minecraft:match_tool",
"predicate": {
"enchantments": [
{
"enchantment": "minecraft:silk_touch",
"levels": {
"min": 1
}
}
]
}
}
],
"name": "fossilsandstuff:cretaceous_fossil_deposit"
},
{
"type": "minecraft:alternatives",
"conditions": [
{
"condition": "minecraft:survives_explosion"
}
],
"children": [
{
"type": "minecraft:item",
"conditions": [
{
"condition": "minecraft:table_bonus",
"enchantment": "minecraft:fortune",
"chances": [
0.1,
0.14285715,
0.25,
1.0
]
}
],
"functions": [
{
"function": "minecraft:set_count",
"count": {
"min": 2.0,
"max": 5.0,
"type": "minecraft:uniform"
}
}
],
"name": "minecraft:gold_nugget"
},
{
"type": "minecraft:item",
"name": "fossilsandstuff:brachiosaurus_raw_fossil"
}
]
}
]
}
]
}
]
}