6 Gemstone (7)
7 Daughter of a sibling (5)
9 Blemish (4)
10 A type of melon (10)
11 Systematic investigation (8)
13 Lusting for money (6)
15 Newts (4)
17 Stones (5)
18 10 10 10 10 (4)
19 A biochemical catalyst (6)
20 Prolongs (8)
23 Anxiety (10)
26 Cornice (4)
27 Inner (5)
28 Related to language (7)
Down
1 In an undiplomatic manner (10)
2 In most countries, it's football (6)
3 City in Yemen (4)
4 Makes bigger (8)
5 City in Nevada (4)
6 Double (5)
8 Swordfish (7)
12 Bumpkins (5)
14 Not essential (10)
16 Provide credit (7)
17 Remorsefully (8)
21 Expression (6)
22 Pertaining to ships (5)
24 Prefix indicating outer (4)
25 Small island (4)