Weekend Ft

[HenHen]

7d- mineral containing carbon in ordinary biscuit, say (9) - ??R???A??
12ac - too many bosses? sadly have to pay one to retire (3-5) - T???????
19ac- odd atmosphere as topless lady hosts at home (9) - E????????
16d- it has ferries everywhere, fret not! (5,3) - ?????S??
28ac- top surgeon's job, belting round theatre (10) - T?E???????

Help appreciated, with explanations
Thanks
HH

[scorpiojo]

12 top-heavy

[scorpiojo]

16 Irish Sea - it has ferries minus fret

[JoolsTwo]

12a Top Heavy

[scorpiojo]

28 T rep anning

[Mamyalynne]

7 Porcelain

[Mamyalynne]

19 Eeriness

(P)eeress +In

[Mamyalynne]

Ore + C(carbon) in Plain

[HenHen]

Many thanks for everyone's help

[HenHen]

Sorry, one more to finish it!!
24d - children's author all but upset dramatist (5) - O?S?N

[Mamyalynne]

Ibsen

almost Nesbit reversed

[bibblebub]

IBSEN

nesbi(t) reversed

[bibblebub]

23a: shirty = s + (t)hirty

[moinonplus]

7d porcelain (ordinary = plain. I don't understand the rest.)
12a top heavy (anagram of "have to pay" minus one letter)
16d Irish Sea (anagram of "It has ferries" minus the letters f,r,e and t)
19a I think it's "eeriness" (topless lady = "her" minus h)
28 I think it's trepanning (top job = boring a hole in the skull)

[moinonplus]

Oops! My first post - didn't notice the previous answers.

[Mamyalynne]

Easy mistake to make,nice to meet you.

[moinonplus]

Many thanks, Mamyalynne; it's a pleasure to be here.

[Aamasamac]

Porcelain
Top heavy
Irish Sea
Eeriness
Trepanning